Hey Bill - A slow fly 10 4.7 should work well. I've been using the GWS hd (the narrow chord props) in a 10 x 6 size with good results. Either one will work as well as many others. I think so far I prefer the GWS hd props. There is more static thrust available and a faster vertical upline which cleans up vertical point rolls nicely. Either way I think you'll be pleased. Try a few out - It's nice that props for these are cheap!
BTW the battery I use is the thunder power 860 2cell.
jon