Running the clinchers you'll just have to:
Increase tire pressure.
Be more careful. Especially watch for edges of pot holes, curbs and other sharp man made bits.
Those pressures would be fine for a clyde on fat sewups, but not for any but the skinny on clinchers.
Keep shopping for the sewup rims, they can be surprisingly cheap. The main market for those now are guys spending for carbon fiber exotica who don't care for the really good conventional wheelsets we need. My most recent was Campy Chorus with Campy Seoul 88 rims and Sapim spokes for $130. The deals are out there.
Old clincher wheelsets can also be had cheap. If you're running 8 speed, let me know I might have a deal for ya.
Ron