ID: Is this Marcel Breuer?  

No.

The shittiness of the arm/back give it away immediately. "Real" classics get better the more you look at them, not worse.

And slotted screws are still manufactured.

It looks like a combination of Breuer's Cesca chair caned seat & back & Mart Stam's B43 armchair frame. The good versions have welded & polished ends instead of an end cap. Do you know who made this chair?

thanks for the answers.

No it doesnt have stamps etc.

you can find these stamped Made in Italy quite frequently. Usually under the seat on the bare wood. And yes, the end caps should not be the push in variety but welded in place.