For good luck, you could toss the lot of them (you got 100 right?) into a pressure cooker for an hour at max pressure. Bonus points, if you can pop the plungers out before they go in so they get the full steam treatment. No guarantees, but better than a kick to the head.
Probably, you won't see the color indicator change, which at least means that they cheaped out on the paper seals. Oh well. BTW I wouldn't really trust most of the other sources either, unless its a medical supply.
For me, it's worth doing this, since if you're going to filter, it only helps if the last thing you filter into is clean.
So far so good! No bad peps yet!