Yes, the problem I have is it I can't really tell which is the fake and which is the real deal
It's relatively easy. when searching:-
1. Only search for used items.
2. Discard anything that says it is supplied/ships from India, even if the ad says it is "used". I can guarantee it won't be.
3. Discard anything that does not show a carrying case in the photos of the item. An OEM Comm Adapter was ALWAYS supplied in a carrying case when it was new.
4. Look closely at the carrying case. Consider the case style, that it carries the Cat Part Number label, and look for it to be well worn.
See this
LINK as an example. I found that in less than 2 minutes. From the photos I would say it is a used genuine OEM Comm Adapter. It's a Series II Comm Adpater so not the latest.
It may be necessary to look for a couple of weeks waiting for one to turn up.