as for sockets doing what i'm describing: try going through some old equipment that's been around the block
you'll find plenty and they don't even need to be anywhere near a leaking battery. some moist suffices to screw up joints between package pins and sockets... then try to get the plcc chip -out- of the socket without breaking the 20 year old socket. either way. better techniques were invented. that better technique is called 'through hole' and 'DIP'. so why bother with anything but that. "muh pick and place robot won't handle dip that easily'. well then hire a room full of chinese kids to do it by hand or get a better pick and place robot.
but having equipment break prematurely (80 years sounds acceptable, 10 years does not) is not an option.
as for wdc fixing the 65c61... what's the problem anyway. the 65C51S worked INCLUDING the parity generator/checker no? they have the plans for that, they had previous production runs of that, so just scrap the N and only make the S again. (or else reproduce the harris 65C51AE (with the 'A' for alternate behaviour as it's better anyway as it doesn't cut off bytes halfway through when the flow control kicks in - that's something harris licensed from wdc no? so just make that one themselves (a bit faster than 4mhz would be nice
they already HAD working chips for decades... they only screwed it up later on. it's a simple matter of sending the old plans back to the factory and telling them to make those.