deans connectors can cost $5-7/pair in hobby shops. I snag them off eBay in packs of 10 pair for usually $12-15. There are the cheaper knockoffs on eBay (their shiny red or black, the good ones are a dull red) and you need to look at the glare/reflections in the pics. Usually they come with heat shrink too.
I got my last pack from this seller, good ones:
http://search.ebay.ca/_W0QQsassZpower.focusQQhtZ-1
Shipped from Hong Kong, almost all of em are, takes a week or two.