Mainnet RPC access for smartBCH is available at https://smartbch.fountainhead.cash/mainnet
Websocket access is available at wss://smartbch.fountainhead.cash/ws/mainnet
You can try using a web-ui with open-rpc playground:
Playground
Remember to enter "https://smartbch.fountainhead.cash/mainnet" as the server URL, and networkId of 10000.
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