Browser Based Fruit Machine

I currently own an online store, but I would now like to develop my brand by creating an online fruit machine in order for customers to attempt to win some of my digital goods. What I'm looking for in the first instance is somebody with experience of writing chance algorithms, possibly somebody with experience of working in the games industry. What I require would likely be very simple for somebody that had produced code for an online fruit machine before, but difficult for a person that hasn't. Simply put, the design will be a simple spin per turn mechanism. No nudge/hold, or any other functions would be required. An estimated twelve prizes will be on offer, an appropriate chance will need to be assigned to each. As far as that attributed chance, a design featuring a back-end on which those values can be manually adjusted, would be my preference. A non-negotiable requirement, would be that at the minimum, all odds should be able to be adjusted according to a single adjustable variable. As far as the front-end goes. I'm hoping to be able to hire somebody who is either capable of designing and executing both parts of this website, or somebody who could sub-contract the other part out. If that's not possible, I'll get the back end developed first & then try to find somebody to make use of the results delivered by the algorithm. So at this point, please don't apply unless you are able to develop the back-end code. Thanks! Hope this can be done. If you think you have the skill-set, but would need to propose a different budget, then let me know. I'm looking for good work, as cheap as I can get it.