Sometimes the right sail will show up at a used gear chandlers. We have one here, so a call might produce a lead... http://www.columbiamarineexchange.com
Plan B (C?) might be to call all of the sail lofts and agents in your general area and see if they know of one or have a trade in to unload.
Thanks Loren, I've been searching multiple sources. This boat must have rig dimensions that aren't quite as standard as some of the others. Unfortunately I saw some posted on here a day or two after they sold. I'll have to be more diligent about checking back.