Replacing American Standard shower fixtures
The plumbing in the master bathroom shower was installed circa 1971 using American Standard hardware and fittings. The current valve assembly uses rubber disks at the end of the valve assembly to control water flow. I plan on removing/replacing the shower set including the valves, but I don't want to have to break into the wall to replace the pipes because the tile is a 1X1 patterned tile that can't be found anymore. The shower (no tub) is a standard 2 handle - hot on left and cold on right. I have 2 questions:
1. Without replacing the pipes, is it possible to use another brand of handles/valves? If so, which ones will work? I'm looking for a 2-handle brushed nickel level style handle, preferably with ceramic disks in the valve assembly. I want to stick with reputable brands (no universal style handles) that will be easy to find parts for if/when something needs replacing.
2. If I have to stick with American Standard, will the newer ceramic disk handles/valves work in 1971-style piping?