Hard to say without seeing hub/feeling condition.
New Business Cycles has 'em for around 260 USD per set -
http://www.businesscycles.com/trcomp.htm#hubs. I've seen 2nd hand fronts go for between 50-80 so a rear is probably closer to 70-120 USD but thats just a guesstimate.
BTW Reload has them new for $150. See
http://www.reloadbags.com/bparts/index.html