Earnst, thanks very much. This is excellent information.
The black and white with the lighter spring matches the HP product pics. I can get green/red ones but it looks like only from Chinese 3rd party suppliers.
For now, it looks like I can take the black and white gears out of the assembly and use them to replace the green and red ones that I'm pulling out of the printer. Seems like, in my case, this should make the old printer happy.