Rear Brake Calipers price/ upgrade options?

["Colin Barfoot" <Colin_Barfoot@msn.com>]

For  rebuilding rear calipers I have found a new lowest price through KVR also 
known as best price warehouse in Ottawa Canada.  They had twin piston calipers 
in stock but not single piston as on my car.   Anyway it is gonig to cost me 
$50 CDN each to rebuild my single piston calipers.
I asked them if I could just upgrade to the dual piston caliper but they 
thought it would not fit. Has anyone done this upgrade ...could you tell me 
how for next time? (It seems I have to do the rebuilds about every 4 years or 
so.)

They also seems to have good prices on cross drilled or not drilled rotors and 
pads.

Their number (they advertise in EC) is 1-800-636-0854