Welcome Roman,
If you make a search in egun.de or a similar site, you can find various Luger books written in German. For any new collector, I think that's the best way to start
You listed two Lugers, both shooter and I would expect them to be in the high end of 'shooters price'. The top one looks to have original bakelite grips, witch alone is worth 60-110 Euros on Ebay, magazine possibly in the same price range. So 450 Euro would seem as a good price for it. But I don't know the prices where you live, as with anything else, it's best to check out the market first.
The term 'Luger' is used on any P08 (or LP08, P04 or carbine), and is not connected to the manufacturer. If you are looking at a mismatched shooter, I would not pay much attention to whatâ??s on the toggle. Good luck!