When I last tuned in several years ago, Ford was still working on fixing the problem with boost gauge failure and was expecting to release upgraded replacement boost gauges that don't fail. Did this ever happen?
They do not show up in a search on the autometer site. You have to call them to order them. I'd strongly encourage you to replace all of the small gauges at the same time to avoid having to disassemble the dash again.
Unfortunately Autometer does not have replacements for the large gauges (speedometer, tachometer), but a member here can replace the innards of your original gauge.