Can someone help me identify this knife?

I picked up this knife recently from an antique dealer, he didn’t know much if anything about it except that it looks like it has a rhino horn handle. The white tip on the sheath seems to be made of ivory or some kind of bone. There is only 1 marking on the knife which a helpful redditor identified as a knights helmet, also that it seems to be a Misericorde-Stiletto type dagger. The blade is dull like a letter opener. It was purchased in the Netherlands but I am not sure of its origin. If someone could identify this that would be amazing, Im very curious where it came from and how old it is.