Last year I had a brake problem with puck brake compound and the disc material I was using..... I called and the rep from Tolomatic said that all the airheart brand mechanical brakes are made by them under that name, also the Wilwood brakes are the same manufacture made by them aswell, just no embedded castings and painted w/logo of Wilwood....
As for the Wilwood caliper, they be sought at your local auto parts supplier, albeit a hefty up charge.