My solution so far.
I was unable to find the source of the coupler on line again.
The 4 local (within 50 miles) used auto parts stores (junk yards) would only sell me an entire steering wheel assembly for $120. This would still be cheap compared to the $250 for a new coupler from Toy. This was much more than I wanted to spend on a Camry with 171K+ miles on it. None of the local auto parts stores (Auto Zone, etc) had a coupler.
I had to try something else. I used a needle point on my grease gun, forced it under the rubber seals on each joint and injected as much grease as I believed it could hold. This seems to have fixed it for now, hopefully another 30K miles. Maybe the car will last that long.
The intermittent difficult turning of the steering wheel has gone away and the steering wheel does return to center without effort.
Hope this info helps someone at sometime.
Dan