You can get a molex to 3 pin splitter!
In any case, don't dual fan the H50, it's not worth it! I get lower temps using the stock fan than I do with two fans, I've tried gentle typhoons, CM R4 Sickles, Black hawks, yate loons, the lot, and the stock fan is exactly the same as dual fan setup, save your money.
My temps were exactly the same before and after using all these fans, I replaced the TIM and cleaned thoroughly with TIM removal liquid.
Maybe it's just my system, but I saw an increase in temps with 2 fans. I even have shrouds to direct the air flow, they did nothing... I spent almost Â£130 on my H50 in fans hahah!
I've learnt now.