Yeh, many variants, some with plastic frame like the CDM4/21 and numbers, both lower and higher, with plastic or Die cast alloy.
The real gems are the CDM4/53 and CDM4/Industrial both built like tanks and used in comercial kit like CD jukbox's.
The Industrial was used in the famous Mark Levinson No31 Transport.
The CDM4/36Pro also great, there are many very good versions and even the most basic was a good mechanism with a glass laser.
To be honest the drawer is irrelevant, as once inside, the CD is lifted off the drawer and there is no physical contact once qued.
The drawer is more about confidence, pride of ownership and pleasure in use, as long as it doesn't rattle and cause vibration problems during play its ok.
This is my go-to site for CD transport mechanisms:
https://www.hifi-advice.com/blog/cla...-1-mkii-cdm-9/
Edit: you beat me to it Barry, with the site reference.