Austrian Mystery Vase - Is it a fake or a collaboration?

I bought this vase 20 years ago from some dodgy trader in Lancs who said it was Royal Dux. I bought it for the look as we were into arts and crafts so it didnt concern me what it was. Now we have moved to a new glass house and need to down size consequently I have been looking at what we have. This is something of a mystery. It looks like a genuine art nouveau piece, definitely aged, worn gilding from handling, very dirty and a very old fine hairline.

The pictures dont show it properly but it bears the impressed amphora mark from the Bohemian Reissner? factory that dates from circa 1912? However it also bears the Mosanic mark of the 3 rifles dating from around this time. Both these factories did work in Bohemia for Max Emmanuel a London store operating at that time. So at a guess I'd say it was some kind of collaboration piece maybe for Max Emmanuel however what is odd about it, is that it bears the words Manufactured in Austria which strikes me as a very mid 20C thing to do. Its a large vase, handpainted and embellished with a basket weave effect gilding.

Any info gratefully received. If you know what it is or any of the marks that would be great.

Nicola.