exhaust merge collector

[qz16]

I have an MSA 3-2 header with 2 inch tubes.  Does anyone have a source for a T304 stainless steel 2-1 merge collector (2.0 inch inlet, 2.5 inch outlet) that will mate with the MSA header.  My understanding is that the MSA header mates with the original Datsun merge collector, but I can’t confirm this because I do not know if my current merge collector is original equipment.  I realize I can have a muffler shop fabricate a collector but was hoping for a less expensive solution.  I found some merge collectors online, vibrant for example but the center to center measurement of the inlet tubes is not the same as the MSA header.  The center to center measurement of the MSA is 2.44 inches, while the center to center measurement of the Vibrant collector is 2.125.  I am hoping that someone has bought a merge collector that mates to the original s30 exhaust.

Thanks for your help.