Seeing as I've thinned my fleet from the days of having multiple 4AG-powered cars to none at the moment, I'm doing some spring cleaning and moving stuff on.
I have a pair of unused 3/8 thick header flanges and one matching 2-bolt 2.5 inch collector flange that I bought from SV3 Power years ago when they were still offering these builder parts. I think the exhaust holes are 1-3/8. These are laser cut and clean except for a couple of tiny surface rust spots from storage. Will fit 20V by slightly elongating one stud hole. Located in Portland, OR, selling all three as a package, asking $25 plus shipping. The collector flange isn't pictured, but it is the same material/quality and designed to fit up to Toyota or aftermarket exhausts at the bottom of the downpipe.