I have been looking to replace the tyres on my bus for some time.
Ideally I wanted some white walls but in the end I just bought a set of Hankook RAO8 tyres as recommended on the Samba tyre sticky.
They look shite like big black donuts, but the ride quality is great., smooooooth
the previous tyres were a bit of a mixture, but also car tyres not really suitable for a bus.
Watling tyres were the only people I could get them from, they were about £40 each.
Next job is to smarten up the rusty wheels and get a set of dropped spindles so I can hide my donuts!