I ran into a snag with my two part mold for my M8 avenger. The rubber coated the whole thing but we don't have enough to make the 1/2 around all sides (due to a slight miscalculation in the size of the box :facepalm) I need to get this done within the next couple days so I don't have the luxury (or the money) to buy more rubber or order anything online. Here in fargo we have most of the large hardware stores and hobby lobby and michaels and what not. I need something to make a shell over the rubber, what would everyone recommend? I'm thinking plaster but I'm not sure how well that would work with the rubber. Thoughts? Thanks!