I agree with "W" for the suffix. Good example in Hallock & Kant p. 135

Joe,

The mis-matched side plate on your Luger appears have a Gothic "S" found on 1934 K-date lugers.

KFS

Keep an eye out for a correctly numbered side plate.
As all are 2-digit, the chance of finding the correct number are quite good. Your 1934 plate will make a good trade or sale.

It's a shame it doesn't have any more identifying features, with it being dated 1937, it would be interesting to see if it ever saw use in the war.

I can pretty much assure you that a 1937 army accepted P08 saw service in WW2. To be honest, that's a pretty silly remark to make.

That does make sense.

How can you tell its army accepted?

The WaA stamps on just about every part.

Plus, the P.08 was a military contract pistol to start with.

Commercial Parabellum pistols have different markings, commercial proofs, etc...

Tell me about that. This PO8 I'm working on was missing a side plate. I'm glad I had metal milling tools around to work on the replacement. Works fine now, but at first.....

Welcome to the forum, and congratulations on your first Luger.

The original bakelite grips were made by a company called Ritzmann and are rather valuable. There have been many reproductions made, so getting a look at the back of these would help us identify what you have. Remove them with great care. it's easy to damage them.

We publish a very comprehensive FAQ PDF document. Just follow the FAQ link at the top of every forum page and you'll find it. It's free and much more valuable than it's price.

With mismatched and hand marked parts, your Luger is considered a "shooter" and you should inspect, clean and prepare it. Use standard velocity 9mm Luger ammunition. 115gn or 124gn should shoot fine if the replacement parts were properly fitted.

The members here have a great deal of background on these pistols. Please take the time to read what we've already shared in the FAQ.

BTW, it's not wise to obsess about trying to return a mismatched pistol to something that appears to be matching. One side plate in 10,000 has the numbers that will match the rest of a pistol. Mauser plates generally have digits relating to the first numbers of the serial number inside the side plate. Besides, the reason parts are numbered is that they were hand fitted at the factory. This helped keep them together during their later service in the field. "Matching" means that the parts left the factory with the rest of the pistol.

There is an art to properly fitting Luger actions.