Sorcha - an Italian neighbor of mine swore by a stick of peppermint gum added to flour and meal to keep away silverfish and other bugs but I have no real experience with that. Just thought I'd mention it.

You can buy the Meal moth Traps at the Gardens Alive website. Go there and register for email notices of deals & discounts and sooner or later you'll get a code for $20 off a $40 purchase or better and you can get them essentially 2 for 1.