dont need to buy a new cooler. ive blown 6 turbos and cooler is still perfect.
just clean it with heaps of pressure and get the bits of metal out.
flush your engine oil too cause small fragments would have most likely passed through the motor.
but u will know when this happens, my motor clunked for about 1-2 minutes after i blew the last turbo. noise went away. cars still purrs, i think im just lucky.