[Roadsters] OT- Datsun Z car bodied go-kart

[chalsted at comcast.net]

I've run across someone in my area who has a 3.5hp go kart with a Z car body...red car on black frame. fibreglass body, not plastic- kid sits in a hole in the roof with a seat, probably around 5' long. has decals for the headlights and grille, etc. evidently there's one in the Datsun Heritage Museum although I haven't seen a pic- anyone have any idea what one of these is worth? I figure there can't be a lot of them around...would be a cool piece to bring up to the Nissan-Datsun meet at the Glen in September. don't want to spend too much for it if I'm considering buying it and figure maybe someone on the list here has an idea of the value. I haven't seen it in person yet. 
Thanks in advance, 
Craig