you can search on www.newegg.com And www.pcpartspicker.com .
Newegg gives much more info on the part than PCpartspicker but the later will show prices from different places to purchase.
Look into the Cooler Master Hyper 212 evo for a cheap cooler that will work well in your case. Currently $24.99 after rebate from newegg. IF you want better cooling, comparative cost but from a different brand look into Cryorg H7 cooler. It out performs the Hyper 212 with a slight increase in cost, around $10 more.