I see your point but I maintain my argument – lots of 3rd world operators are flying 4th or 5th hand planes that are poorly maintained, therefore need parts often, therefore parts from a well maintaned aircraft are in high demand. There were lots of first generation 737-200 produced but the condition of them now means high maintenance. Remember the 737-200 differs quite significantly from the 300/400/500 series.

I also see your point, but the fact is 732 parts are not scarce. Whilst there are large amounts of 732s sitting out in the desert that are past there best and will not fly again, the parts are still there, and individually are usable and are in generally good condition.