[thenewkid64]

One of the things to remember is that the corian type product comes in sheets as thin a 1/4 inch. This could go over (has to) a plywood base. If you do the math right I bet the total increase in weight would be minimal.

Depending on what is below the stove, dropping it further into the counter for a smooth cover would likely be the easier way to go. Raising the counter will add more material, and more weight.