You are aware that only about 500 copies of Magical Chase made it out to the retail stores like Electronics Boutique, Toys R Us, etc... right??? Copies with the box an manual are very rare. Even the Japanese copies of the game are few and far between and seem to sell for over the $300.00 mark.
Japanese copies are not really that rare, they've just gone through crazy inflation in the last couple of years since everyone wants SOME sort of Magical Chase even if it's not the US one. They even did two printings of the game in Japan. It was never really like a bargain bin game, but even a couple of years ago you could score the JP version for like $100 or so.
The same thing has happened with Lickle for the Famicom. Little Samson is a crazy expensive grail so people go for the next best thing and buy Lickle, and look at the prices on it now