this is sold, but it shows that the Sony Plinth has a layered construction similar to the vintage 7 layer JVC Plinths like mine.
https://www.canuckaudiomart.com/details/649187453-original-huge-plinth-for-sony-tts8000-turntable/The only reason I would consider replacing it is for looks. I love the look of mine, inconceivable to change it.
I modified a two arm plinth to fit a 3rd arm for Mono cartridge, see last photo here
https://www.ebay.com/itm/133681838198I can imagine modifying that Sony plinth for 2 or 3 arms: remove the lift handles, saw, drill, hack away hither and thither, then add a ridged layer on top to conceal splinters, bingo!