Every casino operator wants to offer something like this to the community. This is to become standout and the community can differentiate; its very costly to do this, and the amount could go from $50k to $250k. There are many custom casino makers online. I don't want to refer you to do these platforms but rather refer you to this platform for a complete guide on how and where to start. This article will give you an insight on creating a custom casino.
https://whimsygames.co/blog/casino-game-development-cost-step-by-step-guide/

If you decide to proceed with creating one, let us know by making an announcement here; the community wants to see something new and personalized.