Any handgun is not legal to just walk around with up here. The modern replicas are in the Restricted category just like all other modern post 1897 guns in that they are "Restricted" to shooting them at proper gun ranges that are authourized for the discharging of the Restricted category of firearms.
Handguns actually MADE before 1897 are classified as antiques. This means collectors do not need to register them or even to have a PAL (Possesion and Acquisition License which is like your FAL down south). But even with that lack of Restricted status you can still only discharge them at a proper club range. There isn't a loophole that allows them to be carried on camping trips or shot at the local gravel pit like folks can do with the unrestricted guns such as rifles and shotguns. Exceptions to this are antiques that are chambered in cartridges that are still commonly available. .22short, long or long rifle being one and .45Colt being another. Such guns still need to be registered despite being made before 1897.
So when the game warden or customs guy says "not with a handgun you can't" this is sort of what they are referring to. I've got what seems like more than my share of nice handguns these days and quite a few are C&B guns. I treat them just like my other handguns. They are registered as restricted firearms. This means they live with trigger locks on them while stored in my safe/cabinet. To go to the range they are put into a locked transport case with the trigger locks still in place and taken to a club range that is registered as handgun approved. I uncase them, remove the trigger locks, make lots of smoke and even carry them around unloaded in a holster even when not attending a cowboy event. The key is "unloaded". Standard club rules are that no gun is carried around "hot" except at the firing line under the control of an RO running the match. But it doesn't exclude practicing holster draws either. They just need to be done at the line. Then at the end of the day I clear the empty guns again before putting on the trigger locks (a habit I have) and put them back into the locked case and then trundle off home.
Restricteds are not to be carried around willy nilly. Transport is allowed with "reasonable" stops and side excursions for food and gas and accomadation in cases of out of town matches. But the idea is that restricted firearms are not to be carried around regulary. They are always supposed to be more or less going to or from a range. For example carrying restricteds on a cross country trip with the idea of stopping off at a few matches would not be seen as within the intent of the laws referring to Transporting of Restricteds.
Does that help you to understand the situation we have up here a little better?
