1.0 Tightbond glue spread thinly on the sheets.
2.0 Place in sealed handy wrap.
3.0 Placed on a flat clean surface like glass.
4.0 Place thin cotton breather sheet purchased from Walmart in the sewing material department over entire sheeted area .
5.0 Place plastic drop cloth material and seal all around with silicone caulking found at Lowe's or Home Depot.
6.0 Place vacuum source/hose in corner of bag, not on top of bonded sheets and allow drying duration per the manufacturer's direction.

This type of bonding will yield you the highest quality, void free sandwich constructed flat sheet that you are going to manufacture at home, unless you have a press that is. There would only be one thing better to use as an adhesive and that would be a very low viscosity epoxy that you have already stated you did not wish to use.

Vacuum pumps are readily available from many sources including hobby sources, you can even build them from information on line and any avid builder would benefit from having one in their shop.

Bob