I have one almost the same, I assume these were made specifically for gas stations, the buttons are marked which yes could be done by anyone but the marquee flags on mine also come up gas, oil, lube, misc. These would be much more complicated to change out by someone and mine appear to be "factory" done.
I personally have never been able to confirm this one way or the other except to know that National did make a lot of registers "specifically" for companies....ie: specific buttons and flags.
Getting yours "unstuck" ..... sorry beyond my expertise.
Thanks, Z
