Z M Roadster S52 Catalytic converter

Help!

My recently purchased 1999 BMW M Roadster S52 has a mid pipe section that is rusted out at the flanges; upon further inspection, the catalytic converters where gutted and then re-welded into position.

Any one with a used NOS piece? parting out a Z3M S52?

Or is there a reasonable after market replacement?

thanks:cry