From what I understand, the open ended barrel is a lighter version of the same striker dowel. I believe that is a Bocote striker. I have a couple that aren't open on the end like yours is. I'm guessing because I didn't buy the calls new, they were available possibly late 90's or early 2000's. One of the pots I received with one has the original soundboard risers and the other has the newer setup. Both are World Class calls. I have one that is like yours that I believe came with a Woodsman Drop Dead slate that was also used and I don't know what timeframe it's from. Hopefully someone with more specifics will chime in.
I hope you like it, as I like the ones that I have. Maybe not as much as the Black Night ones that I have, but they run good.