I feel sorry for you. Their are literally hundreds of companies in China that make faucets and cartridges. If you cant find a similar cartage at a store you are probably out of luck. I have run across a website that just sells cartridges. But I cant find the link. First I would never use any Chinese faucet as they all fail. I guess it wouldn't be to bad for a sink faucet as they are easy to replace. But under no circumstance would I ever use one in a built in application. Now you have a faucet that doesn't work and tub with the wrong holes drilled in it, not to mention how much work it's going to be to rip out the tub and replace the valves. Sounds like you made an error that's going to cost you several thousand dollars. Always use brand name faucets they initially cost more but most will last 50 years, paying for itself over and over again.
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