
Those are used to hold the tension on the ring (not to "popup" the barrel)
Source you can try the service/parts page but I suspect it'll be hard to find best place is parts on maybe gunbroker.
They are missing on most of all of them I see AND the one you have pictured is a replacement because they don't look like that!
Offhand I don't know if I have a picture laying around or would have to pull a gun, they look more like the thin spring with a flag on the end, why I have no clue. You best bet is to just look around and your probably find something that you can modify to work any flat bent spring metal will work just keep your eyes open when your in the house or garage

Out of curiosity I'm trying to make out the serials but if you have them would you mind posting, I'm just track the frame change these both look like 2someting so they would have the 2nd model frame.
Ah just checked, look at the first post with the diagram I put up, part 24 you see the real shape.