I figure since you FI guys live off of good tuning, wideband o2 is something you would want/need. Anyways, the 5wire o2 that DIY wideband kits need comes from Honda/NGK or out of a 92-95 VX. I have one from my VX from when i went 4wire for a mini-me. Anyways, heres a link to the classifieds for it.

https://honda-tech.com/zerothread?id=311296

Ciao