In the greater Portland/Vancouver area you shouldn't have a problem finding a set of stock wheels. You just missed the Portland fall swapmeet by a couple of weeks.
You do realize that in most cases you can't just run down to the local tire store and have a set of 600 16 6 ply bias tires pulled off the shelf and installed on your wheels an go. They are a special order item in all but the stores that cater to the old car/truck brigade.
Black walls run from about 136 to 200 each White walls run around 20 a tire more
Most likely where ever you order them from they will come from Coker
https://www.cokertire.com/tires.html..._diameter=1777
Old car parts on Powell in Portland will probably have a set of 16 inch wheels but from experience dealing with them they are rather expensive on parts. At least I felt that way when I bought a set of running boards from them a few years ago. I paid their price because was tired of hunting for a presentable set.