Amazon has Colorations Washable Clear Glue for $5 (Reg $15) with free shipping on orders over $25 or with Amazon Prime orders.
Contains non-toxic Polyvinyl alcohol, no coloring additives or acetic odor. Works with most porous and semi-porous materials. Washable, biodegradable and 100 percent safe and non-toxic. Ideal with Colorations liquid watercolor for transparent colored glue that dries glossy and flexible.