Is this a navy luger?

[coosbaycreep]

I've tried researching this luger a lot lately because I was trying to sell it for my dad (I went ahead and got it for myself instead since $650 lugers don't come up for sale in my area very often, plus it will stay in the family awhile longer), but the more research I do, the more confused I am about this gun.

here's a list of the visible markings:
-S/42 on top of toggle
-what looks like a crown with a capital N below it (should be the German "Nitro" commercial proof according to this website) on left side of receiver near where the barrel attaches to receiver
-proof mark on right side of receiver (opposite of the crown proof) that looks like an eagle with some letters or numbers below it. The first letter is a W, but I can't make out the rest of them. It looks like proof number 37 (Waffen Amt (Ordinance Department) proof. Found on receivers of 1930-1933 Mauser and Simson reworks).
-has another small proof that looks like an eagle on left side in front of the toggle
-has a cursive, lower case l below serial number below barrel near the trigger guard
-serial #9475 below barrel
-75 on back of toggle
-75 on top of toggle behind S/42
-takedown lever looks like it originally was stamped 85, but there's a larger 7 partially covering the 8
-9475 on bottom of the mag

From reading on here and other places online, I know it's a commercial luger and it was made by mauser. The barrel is about 5.5" long, which makes me think it's a navy luger, but the rear sights are fixed on mine, unlike all the navy lugers I've seen online.

Reading through some other posts on this forum, I seen another luger that had a numbers matching mag with the same kind of base plate mine does, and someone said it was an east german rework. So is mine the same?

Also, the fact that the takedown lever looks like it was "force matched" by stamping over the 8 with a 7 so the rest of the numbers would match makes me think maybe this is some kind of assembled parts gun or something.

Any info about it would be much appreciated.

thanks