Can waterproof and service
In addition to the list here on RWI, doing a little footwork there in Nashville may yield surprising results. Go to a small mom-and-pop watch repair shop- not a big jewelry chain store. Ask if they are willing to work on "homage watches" or watches with "Chinese watch movements". I have found it critical that you make them understand that YOU realize that this is a cheaply made watch movement that may break during attempted repair and that you will NOT hold them responsible. I have found that many watchmakers do not object to working on replicas per se- it is more about the risk of having to take responsibility for a watch with shoddy movements with parts they may not be able to source.
Don't do it over the phone- go in the shop with a watch that needs some love and explain exactly what it is and if they would take a look- you will be surprised what possibilities open once you build a relationship with a local watchmaker.