Tri-fold girths / sidesaddle community

I am working on clearing out some of the accululated “stuff” in my barn.
I have 4 old tri-fold girths. My understaning is that they are of no interest to the “modern” hunter/jumper, eventing, or dressage communitie, but that they are desired by the side saddle community.

How should I go about selling / marketing / consigning them to reach the community that wants them?

If it makes a difference, I am in northern Virginia.