Need ID of MCM chair in the wild.  

Frankenstein chair?
That...
Frankenstein chair?
That Chair and Base look like they were never intended to be together.

Could be
Very well could be a frankenstein but given the circumstances I didn't feel comfortable getting up there and over turning the chair for inspection.
I was hoping maybe they did belong together and it's just some redone upholstery problem. Many times in the past when I've seen what appears to be incongruent base/chair combo that's been the issue. It's actually pretty rare to find a chair in crap circumstance to be a match up job. Taking the time to match up a odd chair with a odd base, that doesn't fall apart, is a bit of an undertaking and given the circumstances it would seem this chair was tossed before any extreme salvage measures would be undertaken.
The base is what's getting me, who the he'll manufactured it? I have seen it somewhere before.

legs resemble metal craft or ...
legs resemble metal craft or chrome craft-ish to me...I do not think its anything special from first glance but I hope for your sake I am wrong.

It looks to me like a 90s off...
It looks to me like a 90s office chair, not the cheapest line that you would find in Office Depot, but something a little above that. Just a little, though. The upholstery is very badly done and the whole chair part is really clunky in relation to the base. I think some office furniture company simply tried to update their look so they stuck a more sleek, slick base on a conventional chair and called it a day. And now it's on some dude's porch next to his grill and lawnmower, very convenient for sitting on while waiting to flip the burgers.

Nah, I don't think so. It's...
Nah, I don't think so. It's old. It's base is of decent metal, not the cheap stuff you saw on 90's office crap.(But I do know what you're talking about and know exactly what type of 90's office furniture you are referring to)
Don't get me wrong - I don't think its some find of the century or a quality piece just something I saw and it bothered me - it was so odd and I couldn't place it. Just thought I would post it here to see if anyone here might have seen something like it. I think my hunch that's its by one of the many eames imitators of that era is probably correct. If I ever get the chance I'll stop by and flip it over and maybe solve the mystery.
But speaking of actual quality furniture, when I was down in that neck of the woods where the strange chair was at I did find this sweet 1960's Scandinavian credneza from Ulferts (Tibro)at a goodwill. Not that I needed a credenza, but I just couldn't pass this up at the price.

Droopy Eames Base?
Looks like a Eames 5 star base that got too hot and started melting downwards.

it's melting....
I thought the exact same thing. However, and the photo is crap so I know its hard to tell but the chair is a 4 point base. It's like Salvador Dali painted an eames style base.

EST
Ok, was back by the wild chair and flipped it over. There is a mark on the metal base - it reads "EST" in a circle and a "3" is marked on another corner. No other identifiers beside that.
Anyone have any idea what EST is besides a shady, scientology copy cat popular in the 70's?

Mission Creep
You went up to the chair and turned it over. At this point I think you should just knock on the door of the house and ask the owner just to tell you about the chair. My bet is he'll say he made it himself from two different pieces.

I did talk to owner
I actually did knock on the door and talk to the owner. I wouldn't just go up on someones porch and start over turning furniture. (reason I had not last time, no one was at home) She told me she got it 15 or 20 years ago when a friend of hers from (named a ritzy section of town) was cleaning out his parents home. It was an old chair then and He was just going to toss it or donate it to goodwill so she took it because she thought it was comfortable. Knew nothing about it besides that - she's never done a thing to since it was given to her.

.
Ah, okay. I have actually done that--gone up to people's porches and turned over their furniture.
EST may stand for 'established'?

This was the type of place I ...
This was the type of place I figured I might run the chance of being on the other end of a shotgun if I started digging around on the porch without permission. Didn't end up that way, it was a nice woman and her grown daughter, but I feared a billybob with no teeth.
The EST has done zip to help my search due to the exact thing you said - it meaning "established" or even "eastern standard time" The only reason I don't think it means "established" besides no date is that the EST is in a circle - more like a logo design than text. But I can't be sure. I did snap a few pics of the underside of the chair I will post later.
The chair is of decent quality - metal base. The upholstery is nasty obviously because it's been sitting on a porch. I still couldn't tell if it's been redone either - could go either way.

Hope bump
Putting this bizarre little chair back on the radar in hopes some new eyeballs might have seen something similar. Will be posting pics of the underside soon.