I would not really call it common in my experience. I did re-stock one with that shape several years ago(still have the pattern). I have seen many more with the typical fancy back style you mentioned in your first post. This is another style that I have only seen Jeffery market.

http://www.willoughbymccabe.com/imagesDB/WJ%20JEFFERY%20010609%20001_1.jpg


Firearms imports, consignments


[Linked Image from i.imgur.com]