Steve, a set of pre-13 barrels is not much information as there were two types of barrels used then. One would have the joint check and ejector, and the other would not.
The joint check ended around serial number 786xx in 1899.
Members can post barrels for sale and I believe it that if someone saw them on a site it wouldn't be against policy for them to post it here. That would be just barrels or parts.