Try posting on your local craigslist. I put up a listing asking for used rollers and had three people contact me in the first few hours of the posting. I bought a set for $50.00 that looked like brand new.
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2007 Jamis Ventura Comp
2006 Jamis Explorer 2.0
2000 Specialized Hardrock (bought used)
Swim, Bike, Run and sounds like fun