I wouldn’t bother with vacuum bags If I were you. I think it’s fine if you’re using a drying box after the filament has been sitting out a while. Doesn’t hurt to try and find out at least…
Personally, I just use a big plastic storage bin with a bunch of silica desiccant in it. I just busted out some polycarbonate (notoriously hydrophyllic) recently that had been sitting in there for 4+ months and printed straight away; no stringing or anything.
Looks a lot like a carburetor float needle to me. It allows the flow of gasoline into the float bowl, which sets the amount of fuel fed into the engine.
It’s common for float needles (and carb parts in general) to be made of brass, and the wire clip being made out of steel is also consistent with a float needle. The plastic tip is probably used for a better seal when the float is up, closing the needle port.