That would be my recomendation too, however they are discontinued and pretty hard to find. You might be able to pick up a used one somewhere, maybe Ebay? However if you are going to run the stock Tamiya motors almost any ESC would be able to run 2 of those.
Here is a page that explains how to wire motors in series or parallel.
http://www.teamnovak.com/tech_info/H...ors/index.html