Well, I have sold around a dozen or more bows over on archerytalk this year I get a good feel for the going rate of bows. I don't mess with Ebay for bows.
You can find 03 Extremes, Mightymites, Patriots, in that range pretty often as well as other bows too. You can find some pretty nice 03 Hoyts and Mathews in that range too if you aren't set on BowTech.
Now a 04 liberty is still in high demand so they still go for the $400 - $450 range.
I have an 04 Pro 40 for sale and an 03 AR 31 up for sale there now.
BTW, they tested my draw with my anchor point and I was between 27" and 27.5" (this was on a bow without a string loop).
27 inch DL isn't to hard to come by.
Good luck. Hope you find a great deal.