I also would not say "rare", just rather scarce, as all vintage 14" floor toms are. The early 3 ply shells have a definite distinction in tone, while the later 6/9 ply ones will get you a really good Gretsch-like tone, if you can tune and use the proper heads. The shells themselves, due to the woods used, lend a warmth and richness that maple rather lacks. I am not saying maple shells are better or worse, nor am I suggesting the MIJ wonderwood is superior. They each have their own attributes and different tonalities due to the resonant qualities of the woods and sealants used.
I prefer to clear coat the interiors of my MIJ shells with 1-3 coats of clear lacquer, never polyurethane. Lacquer is a wood-based product whereas poly is liquid plastic, which basically encases the wood and lends a plastic-like reflective quality to the sound.
It seems all 14" floor toms are going the way of the wood Dynasonic, hoarded into collections and parts bins, just waiting for the right kit to come along or the highest bid to show up.