Hey GC...It has been a couple of years and the original tires I was looking for at the time were 20" Chinese. The place is Strouhal Tire out on Wallisville Road. I wound up getting different (19.5") rims and different tires from another outfit but below is both their info.
Strouhal Tire in Houston, TX | 9252 Wallisville Rd, Houston, TX
The place I got my 19.5 Bridgestones was...
They were about $260 ea.
Best of luck, hope this helps.