Dagger ID required

[Atlantia]

I've been offered a pair of interesting knives. I've looked through completed items on eBay to ID them and this is the closest I can find. The pair I've been offered are horn hilted (disks piled on tang) clearly of the same origin as the one below, same hilt shape, small button on top of hilt with blue stone in it. but with slightly curved double edged blades in darkly patinated brass scabbards.
Where the hell are they from?
They are quite pricey, but are in perfect condition. Clearly brought back from wherever and stored until now. mint condition.