How do you suggest that I finish "Original Cactus Blank" pens?

I suggest that you use some type of film finish on the completed blank.  This is for 2 reasons.  First, the resin that I use is harder to get a really super gloss so if you are looking for the "wet look" use CA.  Second, I personally have seen "Original Cactus Blank"™ pens made by others who did not put a film finish on the blank and the cactus looked dingy from hand oils.  Remember, the cactus fibers will be on the surface of the pen and I suggest protecting them.  Again, I use CA on everything.