I have an 07 Tahoe and I got a couple picked out. Check the Everstart 48-3 from Wal-Mart. Autozone has a Duralast 48-DL. If you are just bent on getting a deep cell, then get a yellow top. I'm sure they can be had for $200 or less. Welcome aboard!
According to RF TEch, you have 9.1 ft^3 before displacements. With 8 cubes (after displacements I'm guessing), you would need (4) aeroport that are 12.62" long to have a tuning of 33hz.