As we have discovered here that your early bullet box would be uncommon to find a 19 in.
First one I have seen in a bullet box period.
We also know Glock made use of what they had left over. Very common to come across items that are normally associated with earlier handguns. It seems they would just use up old stock as they came across it.
This could explain why you have that particular box.
The box Adam shows is pretty much the standard with early 19s. Again this is based on what I have seen. I own very few 19s compared to the 17s. But I have seen numerous GB auctions also representing boxes with respective models.
I have listed a HB serial number 19. Slightly earlier then yours. I will look at the images.
Is this 19 worth more due to being in a bullet box and labeled for it? I know it is a gift and you were not asking.
A more serious collector of this manufacture might be very interested in this unique sample and pay more for it.
If it sold for more then a 19 in a 4th series box I would only think this was due to a bidder assuming it was older or a collector wanting a 19 in a original bullet box.
The box may very well be worth more then the handgun itself.
Will a 17 magazine fit in that area with the magazine loader?
We know Glock started adding the loader later. I do not know at which point. Could this be one of the older boxes that would not allow the loader to be placed on a 17 magazine?
Early AB handgun (Thanks to GH for sharing)