The Derespina model 10 is also a production version when you see it around $85. Derespina has many different styles of custom fixed blade karambits. His parong style model is also currently available in a production version.
As for production folders.......the Emerson variants (combat karambit, super karambit, CQC-7 karambit, bullnose karambit, and commander karambit) are all excellent depending upon the task at hand. Many of those are good for daily cutting chores as well. The Emerson combat karambit would be the best seller of the bunch. I own all of the Emerson except for the commander karambit. Emerson has recently discontinued a few of these models.
Another great folding karambit is the 5.11 Tarani Master's and Journeyman karambit. I carry a journeyman version everyday to work.
There are many other custom makers who make fixed and folding karambits.
Very soon Boker will also have a framelock folding karambit designed by our own Daywalker. Can't wait to have one of those as well.