Soviets got their jet engines after the war, purchased 5 Rolls Royce engines that were then improved and used in the MiG 15
Everything from 1917 on was pretty much Western technology technical assistance concessions trading with the US, UK, Germany, Italy and other countries-interesting also that they wanted GE exhaust supercharger information that was denied(but they bought GE and Alco locomotives)
Some things were denied but virtually everything in heavy industry came from the west, as revealed by State Department decimal files.
American, UK and German engineers working in the USSR were often victims of contract disputes, bait and switch, and of course many patent and licensing infringements
After the war everyone benefitted from the stolen German Junkers and BMW jet engines, V2 rockets, etc.