1$ or more for CPU mining is pretty ambitious. Especially if you think of the power costs too, which you didn't mention.
The choices I know of are XMR and XZC. ZEC may be fine too.
Leave your computers mine for 10-20 min, see what's the hash rate you can get for those, make a calculation and there you are.
Or, as said before me, go for coinwarz and see if you can find algos where you perform better than this list.

PS. Keep in mind that you may pay more for electricity than what you earn, so it may worth to take a look in that direction too.