I would not buy something that runs on any kind of primer given the possibility of primer shortages and even regulations. In fact, why not buy a flintlock? Really. Rocks aren't going away anytime soon.
That is the story of my life. Actually, you are dating yourself with the whole "grab bag" idea. I haven't seen those in 40 years. There was a little tackle shop around that used to have them and I couldn't wait to blow the $5 I had just spent hours making mowing lawns on some tackle I didn't need (or see).