http://auctions.search.yahoo.co.jp/sear ... ce&auccat=
From the little I managed to glean from the descriptions, it seems that these were made some time ago and marketed through Yamaha's own "aftermarket" brand Y's Gear. I gather that they are no longer in production, but there are a few sets still sitting around, it seems.
It looks like the kits include fuel tank, front mudguard, side covers and tail cover. All items look finish-painted, although only the fuel tank has the decals applied (the decals are included loose for the other items though).
Of course, these seem to be available only in the JDM "RZ250" colour schemes, but that may not be of concern if that is what you want, or are willing to refinish the tank.
The price is a little on the high side (says me who ordered a brand new genuine tank for $250 from a Yamaha dealer in the early 1990s

I would imagine that no problem would be experienced in having these sent airmail from Japan, as the tanks are brand new. However, check with your agent before buying!
Regards,
James