1966 C20 Tires

[1966chevyc20]

Well I think it's about time for new tires. My truck is a 1966 C20 with I believe 16 inch rims (the current tires are a 7.00-16LT tire). I do a little towing not much (just dirtbikes and fourwheelers occasionally), but mostly just normal daily driving. I Measured my current tires and they are about 31" tall give or take a little and I would like to stay close to that height in order to be able to drive on the highway and not be turning really high rpm's. Anyways, does anyone have a recommendation for tires/tire size? I'm also on a bit of a budget so I can't get anything to expensive.