seriously OP, you will most probably get burned. I am a full time programmer and I am not 100% confident I would trust myself to create a gambling page that handles thousands of coins without any fault.
You really have to either have or be an expert in the specialty of security. The site will be attacked. It is merely a question of how and when, and you have to be able to deal with new and innovative attacks constantly, based on whatever platform you're using and things you haven't even considered. Never mind DDoS mitigation and other things that can drive you off your hosting or wipe you out utterly.
In addition, you will need to shell out a lot of money on security and this will just go on increasing as your website becomes more and more popular.