Here's the caliper you guys are looking for from time to time.
Vintage Lil Indian Speedway Minibike Kart Brake Caliper : eBay Motors (item 260598870623 end time May-15-10 18:36:00 PDT)
Vintage Lil Indian Speedway Minibike Kart Brake Caliper : eBay Motors (item 260598870623 end time May-15-10 18:36:00 PDT)