I have a redundant SME 2000 Plinth, modded, very effectively to give the Mass required, with a huge amount of lead sheeting under the top plate section.
It is cut for a Gerrard 401 and SME 3012 tonearm. I can confirm the modification with the Lead Sheet works very well indeed and I was impressed with the results.
With some TLC it could be very nice, the perspex cover is there and has a fair amount of scratches etc. Apparently T-Cut works wonders..
The (apparently, in demand) hinges on the cover are there but minus the springs, (easily replaceable), it was on squash balls for isolation.
Anyway it's here in Barnet (end of the A1 South), waiting for some love (the plinth not me!),
I repeat, in the spirit of AoS...it's FREE
It was reserved for a member but alas he didn't pick it up, so if you want it, it's yours!
Pics of the plinth (with the not included TT or Arm)
without arm and motor: