There is no single brushed motor that comes to mind that is suitable for this, particularly with 10 cells, and absolutely not in a 540 can. I know this for a fact. Unless you plan on rebuilding after every two packs, that is. And you will pay long term much more than just sticking with a pair of 550's or accepting the start up cost for a brushless set-up. My suggestion is to do it right and do it once. And if you can't swing it now, wait until you can.