The plastic buttons on the outside are black, and I suspect are not the original buttons. The epaulettes have OD green buttons which seem more correct. As far as size, the tag is very faded and hard to make out. I think it to be a small. I'm not a very large man, and the coat is quite snug on me when I button it up. If I read it right, it seems to say it is for height of 5' 7" to 5' 8" and breast size 37 to 39. I think it is a small. 

From what I can see on the tag, it was made by Coppley, Noyes, and Randall, Ltd, a Canadian company that made these coats for the US Army maybe in the era of both WWII and Korea. I believe it is marked "49 Pattern." The liner on the inside has some wear, but not a lot. Overall, seems to be in good condition for the age.

Appears to be the olive drab green color. It is heavy and quite warm. 

Make an offer.