Trying to mold Buddha head

[Buddha]

Hello,

I have this 30in high Buddha head and I would like to mold it and create a couple casts out of it. But It's made out of clay and I'm not sure if silicone rubber will be good for molding, because I have a lot of Rebound silicone and I would like to use it for this. I was thinking of using sonite-wax for the release agent, but it doesn't say if it's ok to be used with clay.
Any help is appreciated.

Thanks,
Buddha