You can get plexiglass (Clear Acrylic sheets) in most home stores, as well as plate glass. It might be a good idea to step up to double-strength plate glass because Acrylic is quite easily scratched. Most home stores will cut plate-glass to your requested size, and rubber nibs are avialable to place between the furniture piece and the glass.
Benjamin Moore & Co. makes a Poly-Acrylic in low lustre that would suit your needs on this piece of furniture. It dries clear and has very little sheen. Water clean-up means less hassle and low odor would serve you well. This is something you could use in your garage with the door open and not be too bothered by the fumes.
Be warned, all the Poly-Acrylic finishes are a little difficult to work with. They tend to cloud if you try to apply too much. I'd recommend a foam brush, and work in a systematic way to complete small, adjoining areas at a time. The top I'd leave for last. The durability of most Poly-Acrylics is decent and will protect your investment in your furniture if you don't have small kids like I do.
If you do, ban the Kool-Aid and save your carpet!