I am a first time home owner and have hit a snag in one of my projects. One of the faucet handles in our shower is broken and needs to be replaced, The home was built in the 1970's and I am having trouble finding a replacement. I am wondering if it was just going to be easier to upgrade the handles and stems because I can't find anything else that will fit. I also can not find a name on the handles themselves. Photos below of handles and stem. Any advise will greatly be appreciated.