ore expensive since they have to keep an production line open for your declining demand.[/QUOTE]
Chinese Mig 21 copy is based on Mig 21 F-13, a type which India did not operate in numbers. I guess very few first aircraft inducted were f-13 type in late 60's but for India, Mig 21 saga really started from type 77(FL), Type 88(M), Bis to Bison. Which varied a lot from old F-13 type. Not to mention would have varied a lot from Chinese copy of of F-13. India primarily sought spares from ex Warsaw pact countries or ex Soviet republics after disintegration of Soviet Union. If my memory serves right Czechoslovakia later Czech/Poland was the main source of second hand spares from Cannibalized Migs. It did till, India started producing those parts inhouse.