It's probobly a fake but worth looking into, I've asked the seller for more information about its source and, should he reply, I'll ask him what text is written in the lower right corner.
Notes of interest: PAL cart with a PAL Seal of Quality running a Japanese version of the game with a visable debug menu, maybe used for a preview article or just a well made custom pirate job.
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?Vie...em=190261930045

Could this have been made this way with a fake label?,
http://snesdev.romhack.de/sf2.htm

Even still this would be the unpatched version containing that bug of the random lock-ups and screen flickering i think it was

Be awesome to own nonetheless

The rom could be valid, but that cart is definitely a fake.

Just had a reply from the seller, the corner text reads...
PAL Version
SNSP A3DD DUC
MADE IN JAPAN

Fake cart. Also, it isn't even the final ROM, it's the early Alpha: http://x-cult.org/dispart.php?catid=9&...d=1&artid=3

Compare the in-game hud vs the final one.

Our pic:
eBay pic:

Yeah, the only difference is he's using Fox/Falco's Arwing instead of Peppy/Slipp's one, and he's in a different level. Hell, that IS Fox's Arwing - Falco's has red fins rather than blue.

This is (most likely) what is called a reproduction cart. They are awesome, but not worth prototype hoarder type prices. They shouldn't cost any more than a regular new game from the time period, really. I have the English version of Mother on an NES repro cart, I paid well less than 50 for it. On the other hand, it's possible the guy BOUGHT a repro cart from someone and doesn't know any better.

Well I put a bid in early for it, but realising it's not official, I've asked for it to be retracted. As cool as it may be, it's unofficial and I'm not interested in pirates like this.

Yeah, this is basically what I was trying to say =P

It'd have been better if he'd used the final translation...