Can you identify this 2nd Gen Header?

I got it from an ex-Speedsource car and was not sure who made it. It looks like an RB to me but is not stamped as such. What headers did Speedsource use? Did they make their own? The Speedsource car this came from now runs an LS2.

Thanks.

http://img258.imageshack.us/img258/4...0001cr0.th.jpg

http://img160.imageshack.us/img160/5...0002bv6.th.jpg

http://img530.imageshack.us/img530/7...0003gy8.th.jpg

Hard to say because neither have markings, but it looks identical to my Mazda Motorsports header.

Mazdaspeed unit. Mike at ISC Racing has an identical one that is stainless. Makes as much power as anything currently made.

Isc