This card: www.suruga-ya.jp/product/detail/G3128741
Came from this: www.suruga-ya.jp/product/detail/928058688
Just the Mewtwo: $200
Sealed in VHS: $500
I am going off zero sales data points I know of, so the number is just pulled out of a hat. It may just be a $20 card as listed on the site above. I am more than happy to just pay a middle man the difference to buy that one if someone has a connection.
I think this is the same one if you want to get a PSA 10 for $55
Or if you want the whole sealed set there’s this option
www.ebay.com/itm/Pokemon-COMPLETE-WB-Card-PROMO-Electabuzz-Mewtwo-Pikachu-Dragonite-2-3-4-5-New/233466730131?hash=item365bb39693:g:9wEAAOSwI2xbYWWT
This was just from a quick ebay search, you might find some other better options. I searched for Mewtwo WB Promo on ebay.
Those are the English releases - This one has a different stock similar to the Eevee and Mewtwo Jr Rally
www.elitefourum.com/t/mewtwo-wb-gold-stamp-movie-promo-japanese-ver/22725/1