Most affordable BBK designed for our cars that doesn't completely screw up brake bias are the RR Racing kits.
The SP 4pot kit is available for about ~$800 and the stage 2 6pot kit is available for ~$1000. USD of course. Note that these kits are cobbled together with standardised parts (STI rotor and standard Wilwood caliper) so they aren't ideal but that is why they're so cheap.
Note the rust ring on the inside, that is because the pads don't touch that part of the rotor.
Also, they aren't ideal for bias although not so far off that it's a problem. Finally, they don't have dust boots so they aren't ideal for street driving.