Unknown Norwegian navy pistol

[Morten]

Thanks a lot for all answers. I`m agree that this most likely is a composite pistol with an old barrel. The strange thing is that we can`t find any other pistols in Denmark or Norway with a barrel like this or marked with C5 this way.
The pistol in this thread is from FMU-Forsvarsmuseet in Oslo, my pistol has a different type of flintlock, but the markings on the barrel are similar. My pistol is sent to a gunsmith for some service and to be cleaned.