Not sure what you're paying now, but Trader Horn sells AC filters and so does Advance Auto. Price is $3 or so. If you live in the South Hills area I don't think there are any Trader Horns around. North of Pgh there's one off of McKnight Rd by the Cinemas if you're interested.
There is a Trader Horn a few miles from me but they don't carry the part number AC I need. Just got one from the stealer and it was $12.00. I'll have to check Advance Auto because if they didn't have it, they could order me some I'm sure! Thanks, Ken