Tires for a 93 f150

i got a 93 f150 4.9l 5spd 4x4 and im looking at getting new tires cause mine are shot. maybe 2/32 left. i live in green bay, WI with lots of snow. my stock size is suppose to be p235/75/r15 and i found out i got p235/70/r15 on their now, i got them when i got the truck. im looking at getting cooper discoverer s/t or the cooper discoverer ATR. im looking at getting 31x10.5x15 but i dont think i want to go that tall. does any one know if i can get a little higher size from stock and what would that size be? i could also get the p265/75/r15 which would be a little taller than the 31x10.5x15. if i do go that big i would get the 31x10.5x15 cause they are better built. but yeah im just wondering if their is a little bit taller size than stock that i can go wit so i can maybe fit it on where my spare is or be able to put a stock spare on if i get a flat tire? i maybe do 80% on road driveing and 20% off road.