Harmonic balancer help

Pioneer 872037 is an SFI balancer that appears to have OEM dimensions. I've been running them on my internally balanced 360's for years, but I don't use OEM pulleys.

They are available from Summit and many other sources.

http://thumbs.ebaystatic.com/images/g/Rv8AAOSwRjNXNfG4/s-l225.jpg