Hi Hrtk,
You can either get it from abroad, lots of sellers selling it. There's a guy on ebay who sells skeletal birch ply plinths on four feet very cheap. Or make one for yourself here. Currently my Garrard 301 is in a wooden plinth on an acrylic board. Finyl here on the forum is planning a plinth also and he is looking for a birch ply guy then both of us will make a board. The plinth box whichever material we fancy. I was thinking of getting the motor board made first, putting blocks of wood inside at the four corners and squash balls like the Loricraft plinth. Later on I'll look at getting a proper hollow box made. Currently restoring my SME 3012 arm, will get a Denon 103 listen to the stock one for a while and then send it to Zu for their body and denude.
Regards