Designing Kitchens and Bathrooms - Stripped Shower Handle

I have a 2 handle shower setup, and one of the handle connections is stripped. Unfortunately I do not know the brand and I have no documentation and can not find a brand on any of the fixtures (any advice on how to find out?).

One of the handle became stripped -- when taking it apart I found that a universal attachment (tightened via allan wrench) was used to connect the handle to the stem, and is stripping the stem threading. I can replace with the universal adapter that you get at home depot for a few bucks. The working handle has the correct metal thread -- I would like to purchase one of these for the other handle, but not knowing the brand would not know how to match?

Any chance a bringing this into a home depot/loewes would help me get the part, or would I have to go to a specialty store? Any advice on how I might be able to find the brand of shower hardware I have or find and obtain this specific piece on the net?

Thanks in advance and sorry for my lack of knowledge.
Ron

Ron, if you plan on keeping this set up, you may want to spend a little money now for a longer life. Turn the water off to the house and remove the two stems from the hot and cold water sides. With the handles, take them to the home center or plumbing supply house and get them matched. The condition they are in tells me they may not last much longer anyway, and replacing them may give you a little more piece of mind and the new handles will fit properly from the get go.
Post back if we can help further.

Thanks for the help; I agree that replacement is probably the best route. I was able to find the adapters this weekend, so luckily that fixes one of the problems, but I do feel replacing the stems is the best long-term solution, and will fix the slight leak I have.

The problem that I have is that I am in a 10 unit condo building and do not have an individual unit water shutoff. So for me to bring the stems into a plumbing shop I would have to turnoff the entire building for a few hours. Probably no way around shutting the building down and bringing them in -- any other ideas on how I might be able to figure out the brand without removing the stems?

Also there is a silver cylinder that surrounds about 80% of the stem -- is normal? I'm not exactly sure how to remove this, but I do need to remove to get to the back of the stem, and I think remove.

Thanks again if any additional help can be offered, this board has been very helpful!
Ron