Add to your list of donor vehicles mid 80's full size GM cars (had a '85 Chevy wagon w/305 V8 and hydroboost) and early '90's 3500 series heavy duty vans (have a '93 GMC 3500HD Vandura w/a 5.7L V8 and hydroboost. It is also found on some GMC Topkick truck chassis with an electric backup pump. IE if motor stalls a sensor notices the loss of boost pressure and will kick in an electric pump to maintain boost pressure to the brake system so you can still stop. My uncle's '90 GMC Topkick rollback has this system; works well for stopping a 26K truck...
HTH,
Nick
HTH,
Nick