How about buying either at the stores of branded goods manufacturers, or their certified outlets?

Buying very expensive brands from Amazon is an invite to get a fake since no reputable brand (in the very expensive segment) will use Amazon as a retail channel.

Even with lesser brands you run a super high risk of not getting the real thing.

This story[1] is a reminder of what you're likely wind up with. Upon reading it I was just shaking my head and thinking "I could have told you so"

[1] https://www.theatlantic.com/technology/archive/2019/01/count...