Note: the PAL version of this game is not nearly as rare as the NTSC version. The rarity also makes the cartridge and package a particularly tempting target for forgery. Make sure you know what you may be buying, as well as what you may be trying to sell. With the recent news explosion surrounding this game, there are plenty of fraudsters about.
Check out this nifty Visual Guide to Buying Stadium Events from NintendoAGE in order to help determine whether your copy of Stadium Events is worth anything.