It's a long while back that i got it now. I do remember that it was a bit of a silly amount considering it isn't boxed, the manual is just a photo copy but it does have the map. It is the USA/CAN NTSC version though in english which seems to be a lot rarer than the JAP version - and easier to play for non Japanese speaker, lol.
I think I got in a bidding war and didn't want to lose and ended up paying somewhere over 50 but less than 70. I played about 10 hours or so, then my save game disappered so I assume the battery died and i've never got round to replacing it. That's probably the most expensive old console game i've ever bought, they're all in the loft at the moment though and i'm not even sure what else i've got.