If it was me I'd get the RC-10s.
What I did was get RC-10s front and RC-mini surrounds since they come with mounting brackets. But I got cherry color which are much cheaper ($99ea) than the RC mini in black. Unfortunately the cost of two RC minis in black is more than a pair of RC-10s so it makes no sense for you to buy them.
There is no right answer to your question. If you want bipole/dipole speakers, get the RC-R. If you can get them for $245/pr that's a bargain. They usually cost that much each.
Since it looks like you'd have mounting problems by your fireplace, maybe the RCR would work best for you? You could place it flush on the fireplace ledge and the other other flush on the wall.