I looked at my bathroom scale the other day and realized that it was made out of a sheet of 303mm x 303mm x 8mm of tempered glass. So I went on Amazon and picked up a second one.
Removing the sensors stuck to the bottom of the glass was done carefully with a few flat screwdrivers and some patience. A hobby knife and WD-40 were used to clean off the excess.
Here's a link if anyone else is interested:
Keep in mind that this is tempered glass (I've used the original for years without any problems), so it has some heft. Tempered glass doesn't have the same thermo properties as boroscilicate, but at 8mm thickness compared to the thin mirrors other people use, this is a fantastic upgrade for the price. Bonus points: all the edges are radiused.