How many of us are there? Owners of Dodge based RV's?

Well i bought a 1976 dodge brougham(sp?) 21 foot yesterday
pretty nice, now i need help getting some parts, it needs tires bad
looks like they are 8X16.5, can i get any bigger, what is the best brand?
i have a ton of question so i can take this in another thread if better or exchange emails with someone, mick@roseint.com
thanks and i look forward to the fun we are going to have
Mick