Your other option is to make the "collector`s item" part of your brand identity--your unique selling proposition, or USP.
Lots of people sell toys, and there even are a lot of toy barns. But
how many of them are made out of real wood? Then, how many are made of
100 yearold wood?
I don`t think this actually is a "collector`s item," in that you won`t
necessarily be selling whole sets of these barns. You could do it,
though, setting aside semantics. On the other hand, you also might look
at the antique market, "vintage" cateogries, and history buffs.
Another thing that comes to mind is that Cabbage Patch doll. Each doll
came with a history, and I think a birth certificate? You could sell
the "story" that comes with the barn as your main product, with the
barn itself being the illustration...the secondary item.
Wow, thanks everyone. Wish I`d come here sooner.