Microsoft Wireless Comfort 5050 keyboard and mouse

With due respect, look at the system requirements for the keyboard and mouse and see if your iMac has the bare minimum. You can find that information by clicking https://www.microsoft.com/accessories/en-us/products/keyboards/wireless-comfort- desktop-5050/pp4-00001#specsColumns-testCarousel

My guess is yes, however you were not specific about which iMac you have so I cannot tell for sure.

As mentioned I think it will work, your version of OS X is considerably newer than 10.7, so you will have to buy it and try it and if it doesn't work then return it.