A FWIW comment:
If you're new to horns made before, say, 1946 -- and excepting Dolnet -- you could get horns with a variety of intonation standards. The current most common standards are A=440hz, called "low pitch," and A=442hz, which is a European orchestral standard. The reason I mention this is because unless it's specifically stamped "low pitch" or "A=440" or "A=880," it's probably some other intonation standard and these horns will not play in tune with modern instruments and cannot be made to play in tune with modern instruments. That's particularly the case for instruments that you even think were made before 1914.
I don't know much about flutes, other than those from Claude Laurent, but it looks to me that the headjoint is a fairly old style. Also note that there were Db piccolos.
Any particular reason you're interested in this one, aside from the fact it looks cool?