Weight, Clamp or stabilizer?

I am interested in the questions from the OP. I also have a vintage Pioneer table (PL-530) I bought new in the 70's. Have used different cartridges over the years and am now using a Grado Gold.
Aside from playing less than flat records I have an interest that pertains to the table feet. The feet on the PL-530 are just plastic ones that have no isolation capability. But most important, there is no adjustment for leveling the table to a close to level state.

My question to those who may have experience with these vintage tables.....My house is well over 100 years. Floors are anything but level. To obtain balance of the table I have used thin shims on each of the 4 corners to achieve as close to level as possible. Besides the capability of isolation, does anyone know if feet with isolation properties as well as adjustment for height available??

chakster....Thanks for your recommendation. From what I've found, the AT-616 isolation feet are no longer in production. There are some sites that list used ones of a price from $600 to $800. More than double the cost of my table and cartridge.

So....Would the cost of the feet really be worth it given my setup? If I had a more costly table and cartridge then, maybe. I realize that setup is most important for any table. I am looking for a modest tweek that may or may not yield any sonic improvement. Certainly not high dollar feet meant for more exotic setups. Thanks anyway for your input.