That type of plywood is not what you would find at a lowes or Home Depot. It's usually called baltic birch plywood if you are talking to American vendors. Its certainly more expensive but it's a fantastic product when you need stability. First of all, it's solid with no interior voids, and secondly, it's made from uniform plies of birch, allowing for a wide availability of thicknesses as well. Normal plywood is a core made of cheaper material that is capped with a very thin layer of veneer. Baltic birch ply, being the same thickness from ply to ply, works much more like lumber than most plywood.
The bass looks great by the way. I'm not in love with the shape personally, but it looks really clean and the plywood makes for a great look. The laminations really look good with that extended body shape.