Hey there, i'm in the same boat, looking for FE7/8 since echoes rekindled my love for FE/TRPG.
I'm wary of the pressed number since last week Natalie, just got 2 bootlegs (7&8), bought them online on impulse because i could see the numbers next to the logo on the picture sadly they are fakes :
number indented is 11, they dont "slide" when i opened them and the pcb is kinda naked with the infamous black resin blob and a pokémon serial number.
If you're buying in a store or some flea market (or online with some HQ photos) you can check the numbers on the front usually next to the title like Natalie's + the ID ( AGB-AE7E-USA or AGB-AE7X-EUR) and the pins/pcb. (if you look at the pins/connector you should see Nintendo AGB-Y11-01, my fake is E05-01 aka pokémon)
Ultimately the only way to be 100% sure would be to unscrew the back and check the PCB.
Here is a legit FE7
(image taken from French site http://discourse.viensfairetesdevoirs.com/t/listing-photos-des-pcb-originaux-sur-gba/175 )
And the two fakes (from my old nokia toaster phone)