Eames Aluminum/Evans Products Co. "Mutt" Coffee Table (Missing Glide)  

Either way, it is Eames and uncommon.
As far as the glides are concerned, it may not be worth trying to hunt down an exact replacement. There are off-the-shelf black or white glides that can be used as-is or modified to resemble the originals without too much effort.

Wonderful Suggestions
Great suggestions and I'll certainly take them under consideration.
Thankfully Graham did say he has an Ever-Level glide matching mine so it looks like that search is over. Haven't had too much luck with the local Herman Miller dealer who looked through all their old stock and found nothing.
There's also the possibility that it might of been specified to fit a particular space like the corner of a reception area.

Very likey
I agree. It's entirely plausible that the table was made as part of a group of furniture for a reception area. I'd even bet that it was to be used with some Time-Life chairs. I've only ever seen that base on early Time-Life chairs. It did not last long as it was soon replaced by the version you see in use today which was also used on the aluminum group chairs replacing the four-star base with the flat top. I think the addition of the adjustable height and tilt functions precipitated the change.

Good call Pegboard
That base was unique to the time life chairs at the time of their intro. in 60/61

glides
our base looks like the 4 star base of a German Times lobby Chair with the fixed base, you should get something to match at Guy Ramond, you'll need 4 as they will have black with screw threads, not exact as component is manufactured more simply, your glides look like the metal glides on the eames recliner that Mancha has on his spares page.
regards matt