I just picked up an ORIGINAL set of H-O Racing tri y headers today!!!!
Check em out
http://rides.webshots.com/photo/2216...34160182YCPxSY
or here
http://rides.webshots.com/photo/2942...34160182TtepGb
These are d port headers, but since the tubes have to be heated and formed to the "d" port I would imagine they could be heated and re-shaped so a round port flange could be installed on them, get them coated and away we go. If adapting a round flange is not feesible then here is a pattern to build another set.
Actually with all the troubles here I was thinking about producing specialty headers and tri y's myself but time and space are an issue, that is UNELESS I can rent that new office that has the shop out back, THEN I could..............

wait a minute, there I go day dreaming agian.
I am SO glad to have happened across these headers today, I had a set back in 87 or 88 and really loved them, along with all the other H-O racing stuff I had, I used the dist. and carb accuracy kits, HC-02 & Rhoads lifters, ported the heads by their book and spec'ed out the entire car per their recommendations, ALL good stuff and that car would RUN.
Ken, I spoke to you a few months back about this project, I still have your number, you'll be getting a call before too long, thanks for the advice.