The whole thing about the best dd's from the 70's was the acoustic feedback issue. Some howled with little provocation, where the heavier ones could add a form of bass 'heaviness' to the sonics if incorrectly sited.
I see now why you want to sell the PL71. Not sure the Sony arm would like low compliance heavyweights though.
By the way, the 8750 complete with fluid-filled mat really is reference class IMO. We had one at KJ and couldn't sell it due to the LP12
I doubt many were ever sold in the UK, but maybe in Germany and the US things are different?
I can't go on and I can't go back, I don't feel so matter of fact,
I tried and tried to make good sense, What's the good to try it all again?