so to clarify something... you can run a single chainring on a double crank with NO PROBLEMS. all you need is shorter bolts and to not give a **** if someone cares that you have a tiny little lip sticking off the inside of your spider arms.

that said, if you are still taking affordable recommendations, i bought a set of shimano 105 (double) cranks off ebay, brand new, gloss black, for $40. i then bought a chainring for $15 and i've had no problems whatsoever. if you feel like you need to not have that lip on the back, then there are a lot of good recommendations in this thread, but beyond that little lip there is NO difference between a "track" crank and a "road" double. (144bcd excluded)