Hi Frank,
Most of the photos I collected and posted, above, were just associated with a sales or auction house ads that appeared on the Internet over the past 2-3 years. No mention of whom actually did the engraving work.
You might check out these engravers' association web sites :
http://www.fega.com/
They have a big annual convention each year in Reno. NV...just happened last month.
Here is another link :
http://www.grstrainingcenter.com/instructors.html
This photo scan was from a nicely done luger carbine showcased on the cover of the German Gun Collectors Association magazine.
I bought back-copy of the magazine through their web site :
http://www.germanguns.com/index.html