Does anyone make a slip-fit (no flanges) HFC?

I just picked up an older Buschur TBE with a test-pipe, and I've been having trouble finding a HFC.

 

The current Buschur hi-flow cat is flanged on the front and slip fit on the back. I would imagine they would be willing to modify their cat and custom make it slip fit on the front and back if that is what your DP requires, I am assuming it is not flanged. They may even do it at no extra charge. Even if they charge, I can't imagine it would be much. I would just call and ask.

 

Good idea, I hadn't thought of that.