Just picked this up from Wikipedia:
In 1945 seven locomotives were taken over by the Soviet Military Administration when they occupied their zone in Austria. These locomotives, 12.002, 005, 006, 007, 009, 013, and 12.101 had T (Trofya) painted before their running numbers and marked CCCP. The Russians did not transfer these locomotives out from Austria and when they withdrew their Occupying Forces in 1955 the locomotives were returned to ÖBB in September 1955. When the main line west of Vienna was electrified, all ÖBB 1D2 locomotives were out of suitable work for them. They were taken out from service and were written off from books.
So it does appear my loco isn’t technically Russian. Bah, humbug. Its got CCCP up the side, its Russian!