I hope your carb repair works. If not, and you intend to keep the machine, I'd suggest looking into a new engine if your only other option is a $225+ carburetor. The Simplicity website lists its lowest-end Broadmoor at $3,699, and your current engine is 20-ish years old.
One nice thing about most tractor and zero-turn mowers is that there is a lot of flexibility with engine replacement; they don't require the precision fit of a car engine, and are far easier to install. At worst, you're looking at perhaps a different size drive belt and modifying a wire harness.
FYI, I have a lot of experience with this. I've been in the professional lawn service industry for 22 years, and just yesterday installed a brand new Briggs engine on my mower, which had a Generac one before (which detonated last Wednesday).
Good luck, and let us know how it works out!