Here's some information I found out...
At least I know where to start. After some serious research
The rear hubs are the same, the brake hoses are the same, the e-brake cables are the same, all you need is complete rear calipers, pads and rotors. The rear calipers list for $340.63 each, they're new and include brackets, and will cost you $223.40 each. The pads list for $48.05 for a complete rear end set, including all the spring clips and such, and cost you $31.19 each. The rotors list for $110.00 and cost you $68.00 each.
Rear Calipers: $223.40 (446.80 for both)
Rear brake Pads: $31.19 (62.38 for both)
Rear rotors: $68.00 (136.00 for both)
TOTAL FOR PROJECT USING ALL NEW FACTORY PARTS
$645.18 before shipping.
Not bad. It's a definite starting point.
http://poweredbytoyota.com/ will be my parts provider.