Not an A-type nor any other Original Mauser, Oberndorf commercial rifle any more, as it is now. Most likely put together quite recently from mostly old parts. The stock is not Oberndorf, but rather Suhl/Zella-Mehlis style. Such cross keys in foreend usually came with half-octagon, ribbed barrels. There is no sense with the round barrel. The open sights are modern, non-German. The scope is attached with a 1920 ex - Reichswehr (Versailles treaty 100 000 men army)sniper mount. These were surplused and sold off about 1930. There is no stepped receiver ring. What you see is the flange of the barrel, in front of the receiver ring. Here in Germany such a pasticchio would be about Euro 500.- at best.