Thanks for reminding me Lee.
In Gatherings past we have offered “for sale” items. What I think has worked best was if individuals posted what they might offer. Then if someone posted an interest the seller felt it was worth packing up that item and driving it here. The reverse might work, where someone posted a “wanted to buy” wish and others said they had that item or something similar and would bring it. That I’m guessing is more of a long shot, but if it works, great.