AK Used Tires in Tampa, somewhere in Drew Park. Supposedly they have 4 Bridgestone Potenza S0-2's there in my sizes, with 75% tread life, and for $36 each + mounting. You may be able to just kick through the inventory until you find a nice matched set of cheap/sticky tires. I'll be stopping there today or tomorrow and will post back if it's worth a crap.

Used is the only way to get the results you want on the budget you've set.