would you buy a used airplane...
The Argentinians did not have much luck when buying a used cruiser from the Americans, even if it had a good pedigree from surviving Pearl Harbour..... maybe they threw away the lucky rabbit foot.
History is littered with large countries selling arms to small countries, then charging exorbitant prices for spare parts. Given the Russian need for currency of any sort, wonder how much it would take to keep Fencers airworthy!!
Rules of war... don't mess with the Balkan countries, do not try land assaults on Moscow, and do not buy anything from the Russians except Kalashnikovs