Luger identification & repair of sheared off front sight

[Hmelarousy]

Good morning!

Calamity has struck: I purchased a Luger at a P08 Long , Artillery Luger. When it arrived I noticed 2 things:

1- The barrel was shorter than a previous Artillery Luger I have

and

2-the sights on it were not those of an artillery not Navy. Just a front sight and a back v notch sight.

Then to my bad luck I take it to the range, it falls and the front sight shears off and I can't find it.......

Can you help me identify this Luger and also tell me how I can replace the front sight since it seems to have shared off?

Also doe.it seem that at some point it had an artillery sight that was removed and the barrel reblued

Thanks!