Etsy.
I just put the bits I find into a container & save them up. A friend has a smallish 'Pirates treasure chest' that he puts it all into & his kids ( now Grandchildren ) have fun playing with it.

The treasure chest itself is a neat home project & you can use pallet Wood, used wooden bed slats, plywood, eBay for the locks & hinges, metal packing strip for the metal straps.
Glue & line it with velvet after some woodstain, heavy varnish & black / brown paint.

His is very similar to this one, but painted up & crush velvet lined.