Sorry to enter the fray rather late on the brake subject, but there is a company in Bromsgrove, BG Developments I think, who produce replacement wheel cylinders CNC machined from solid aluminium in a range of the larger sizes, great for the front but not so good regarding the rears. I believe that these incorporate modern seals and pistons and are thus ultra reliable, as well as slightly lighter. To me the only downside is that they look to exactly what they are, beautifully made from billet, not a casting mark in sight!
Neale Shepherd