Genevieve,
Uline.com has larger resealable bags (2, 4, 6, and 8 mil). I think the largest in 4 mil is 30"x30". If you need a larger size, Uline also has poly bag sealers (tabletop and handheld), as well as poly sheeting in different thicknesses. We have needed to enclose pieces of wood furniture for bug treatment and we have used this method to completely seal them up. The handheld sealers do have a bit of a learning curve. If you heat the plastic for too long, it melts too much and makes a hole. If you don't heat it for long enough, it doesn't seal. So if you go that route, just know that who ever is enclosing the objects might need to practice to get it just right. I have heard of other methods for household use where you heat knife and put it up against the two pieces of plastic and it melts and seals them together, but that sounds a bit dangerous to me, especially if you need to cover something large.
I hope this helps.
Anna
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Anna Graff
Conservator
LDS Church History Museum
Salt Lake Cty UT
(801) 815-7089
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