If you have lots of money, why not draw up your own spec of exactly what you need (big wheels, brakes, etc.
), then start looking in catalogues like Metro
If you don't mind the "industrial" look, you could even go for a folding
Actually, there are many variations available. As I say, if I were you I would design my own, and then (either build it myself, or...) spend a bit of time on the web!