You can't make them as cheap as a private mint. It would cost a fortune for the die making machines, as well as a minting press. Even if you did the ancient thing of two dies, a pair of tongs and a hammer, you still have to know how to harden the dies you make. Go get a book on the minting process and you will see it is not an easy think to do and it is very expensive. If you are any good at making molds you can cast your own tokens. The Chinese cast billions of cash coins using sand molds. I commend you on wanting to try but the cost of your own mint will be expensive and casting takes a knack. Good luck.