That's a bit of an oddball part, because it seems it was only used on I6 cars from '65-'66.  My first '67, which was an I6  I robbed the power steering from, had the conventional V8 system where the center link threads directly into the control valve.  That same system was what V8s used in '65-'66, but for some reason the I6 cars used this short link between the valve and center link.  Basically the holes line up with the holes in the center link and the left inner tie rod end and the assist cylinder sandwhich this link and the center link together.

Long story short I'd bet $1,000 that you aren't going to find one of these at any of the places selling new parts, because its obsolete and they would never sell enough quantity to make reproducing it worthwhile (I6 only for two years).  So, I would reach out to Cedar Valley Motors in Austin, TX.  I was able to get the right pitman arm for my '67 when I converted it to Borgeson power steering.  They carry a lot of good used parts, which I think at this point is your only real option.  Phone then at 512-288-2569. 

Or, if the threads are not totally boogered you could work then with a triangular file and remove any offending burs, and reshape the threads.  Don't worry about any material that gets lost; the threads don't hold this pat in place they only exist for adjustment.  The clamp is what really secures it.  I would probably try this first, because its free, and you have nothing to lose at this point. 

Call Dan. But I think he's heading south for the winter, so do it soon.
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