Games galore

I want to develop a website game where players log in and play a game they pay for. they pay info is stored and can be reused every time they want to play more. The score is tracked and the points they earn can be traded in for merchandise. The game I have in mind is a shooting gallery where the target 'floats' around and players move 'crosshairs' and shoot at target. Initially I would only wont this game and then additional games. the proceeds from the game would be tracked and divided between two organizations. I have no idea on a budget at this time.