Can you help me find a fantasy tire in real life, or one that's close enough to what I need?

I've already asked this, but none of the previous answers were enough to get a tire with. I thought I'd get better results if I described the tire better.

I'm making a fullscale replica of a vehicle, and it needs a set of wheels/tires.

Here's a rough draft diagram of the wheel (cutaway), along with dimensions on it..

http://www.deadguy.net/images/Fantasy-Wheel.jpg

The dimensions shown are "absolute values", but there's leeway in choosing something that's close, feel free to round them off.

I recognize that a tire/wheel of these exact specifications is not likely to exist. I can't do a custom tire/wheel, so I'm trying to get as close as possible. I suspect there might be something out there in terms of construction wheels, or extreme offroad wheels, but I can't seem to get enough info on what it is I'm looking for.

I need a full tire spec and supplier, for rims and tread. In other words, I need to take an answer and use it to go buy an appropriate tire. Anyone?