These first started showing up on the surplus market in the early 90's I think it was.
Then as the supply dried up, like everything else they became more 'collectable' in ways.
They got some attention from the true Walther collectors and recognized as a continuation of the Walther PP production or better said,,a copy of it.
The Chinese made a copy of the PPK pistol in the 1960's I think it was and very very few made it to the USA before the GCA68 banned importation of any PPk style/size pistol.
Those are seen as part of a Walther collection even though not made by the German company obviously.
These E German PP copys have begun to be seen as having a place in a Walther collection as well. Their 'history' of having been made on captured Walther equipment doesn't hurt their story either.
Though not nearly as rare as the Chinese made pistols, they're not the hard to sell under $100 gun they were in the '90's.
I don't know how many were imported.
From what I recall they are a strict copy of the Walther PP,,maybe w/o the loaded cartridge indicator. I think some of the late production War-time Walthers were made w/o that feature too.
Fit is at least to War-time standards of the original Walther,,the polishing and bluing usually left something to be desired on them though w/some rounded corners and over buffing.
Markings differed and that set the stage for the guessing game of who did what to them and where & why that I posted about earlier.
They do what they were made to do and usually shoot quite well.
I never compared parts side by side w/a Walther but the assumption is that parts will interchange. Some handfitting would probably be needed.
IIRC the last time I saw one of these for sale (about this time last year) it was priced at $300 or $350. I don't know if it sold for the price(s) or not.
They are not at all commonly seen anymore for sale if my gunshow and shop wanderings are any indication.
That may be due in part to a low number originally imported. The unusual markings makes ID difficult for many and perhaps these just don't go up for sale that reason,,I don't really know.
You can check the net auctions for them and see if they have sold. Try different versions of the mfg'r and the markings to find them as they may be listed under most any of them.