which Marshall of the CCCP was the owner of the uniform?
He was WW II veteran, had the rank of an captain or major or something in this region and fullfilled a lot of heroic deeds: Kutuzov 3c, Nevsky, GPW 1, GPW 2, and 2 or 3 Red Stars - that's something. The Lenin, Red Banner, GPW 1 (1985) and 1 or 2 Red Stars he might have got for long service.
Christian, save your time: the ribbon bar is NOT of the marshal CCCP which the uniform belonged to. The seller made this in order that no one could identify who was this uniform belonged to.
There is, however, a hole, made for HSU gold star medal.
anyhow, the ribbon bar looks authentic and not mixed together (like in all Hollywood-films). But you are right: There are actually no marshalls of the CCCP without HSU.
Christian, making a ribbon bar is the easyest thing. Believe me, I cheked the book "marshals & fleet admirals CCCP" (K), there is NO marshal with this ribbon bar.