5.5" Model 629-3 Unfluted Cylinder - Import Marks???

[THREEDFLYER]

So what are these marks on the underside of the barrel on this 629-3 with 5-1/2" barrel and unfluted cylinder??

 

[P.44]

Looks like Belgian C.I.P. proofmarks to me.
Here are some more:
Finally arrived

P.44

 

[THREEDFLYER]

So do the marks indicate this gun would have been sold to a foreign country for military or law enforcement of just a civilian gun that was sold out of the USA??

Would a factory letter from Mr. Jinks reveal more details??

I assume not because it was probably shipped from a distributor after leaving the factory.