to install or not to install

[jasin]

we have a problem. the grooves on the inside of the handles to the shower have been stripped and we can no longer turn the hot water on, it just turns. in addition, another one of the handles broke where it connects to the fixture. the owners want to replace the plumbing system, t-junction thing and everything. it's a 40+ year old system by gerber.....what can we do to solve this problem

[LonnythePlumber]

Buy new handles and repair the faucet. The pot metal handles do strip out. You will probably need to take the stem with you to make sure you get handles that fit. Avoid one size fits all handles with adapters.

[e-plumber]

we have a problem. the grooves on the inside of the handles to the shower have been stripped and we can no longer turn the hot water on, it just turns. in addition, another one of the handles broke where it connects to the fixture. the owners want to replace the plumbing system, t-junction thing and everything. it's a 40+ year old system by gerber.....what can we do to solve this problem

Replacing the handles and possibly the stems would be the quickest fix and Gerber is very common, so finding the replacement parts will not be a problem.
If the owner of the property wants to replace the complete shower valve, let them do it. The new faucet that will be installed will be a pressure balanced faucet that will meet code requirements and protect you and yours against scalding :)