Wow, first post in more than 5 years.Long time no visit. H-factory itself has closed so getting parts directly would be impossible. As I don't have a H-Fac PAM243, can't test it but as the latest PAM243 models from Noob and H-Fac are super rep level, there is a big chance that the two will have interchangeable parts. No guarantees though.
As for the movement parts, I doubt any TD would be able to source you a part for an A7750 movement.They are not Ofre or Cousins. You could try asking for the entire A7750 movement. They've been around for years I'm sure the factory has extra ones they'd like to sell. Plus replacing the movement would probably be an easier repair then use the old movement for parts should the new one break down later.
Good luck!
