I just did visit Singapore and was able to find some amazing dollar sized coins in ChinaTown. I would recommend you visit it and ask around for coin dealers. They're everything you need there.
hard to get big coins where i live.
got these arcade tokens today but they're good at most for the matrixes.
3inch jumbo US half dollars would be too big.
2inch should be perfect.
now if i can just find some in singapore.