I'm not a good mechanic and didn't even know a torque converter was a thing until now. But, I did find some places that seem to carry compatible parts:

Not quite. If you look at the parts linked, both say they are discontinued and no longer available to purchase.

Hope you really don't need it.

 

Their own TSB states
“BACKGROUND
A judder from the torque converter lock-up clutch may be felt while driving between 20 and 60 mph. The problem is typically diagnosed as a bad torque converter. American Honda investigated the judder and found that the torque converter was not causing the judder and the transmission is not damaged by this judder.
The judder was caused by deteriorated transmission fluid. The transmission fluid deteriorates quicker than expected when it is exposed to intermittent high heat loads under specific driving conditions. A software update is available to maintain the transmission fluid temperature within the desirable range under all driving conditions and eliminate the potential for this judder.
There are two bulletins referring to this subject:
• 17-043 - 2014–17 Odyssey: Judder from the Torque Converter Lock-Up Clutch. Do this bulletin first to apply the
software and flush the transmission as indicated in the REPAIR PROCEDURE.
• 17-044 - 2014–17 Odyssey: Judder from the Torque Converter Lock-Up Clutch After Software Update. Some vehicles based on how they are driven may still experience ATF deterioration after updating the PGM-FI or A/T system. In these cases, do the inspection and, if necessary, flush the transmission as indicated in the REPAIR PROCEDURE.
CORRECTIVE ACTION
Check if the software has been updated.”

http://www.urvi.net/forumfiles/SB/A17-043.PDF

As others have stated, a 3 time drain and fill can work wonders, especially if your fluid has been heated by trailer towing. There’s also been an issue with the 3rd gear pressure sensor on these, mine included. It’s an easy replacement to do.

 

Transmission cooler 100% a must if towing in the Ody (edit) if you don't have one installed already.

 

I'd start with the software update and 3x drain and fill first.

 

Independent mechanics typically get parts from a vetted vendor in which they can return parts if need be, and not use vendors who cannot back up returns if they are sent the wrong part. You could discuss with him buying the part yourself, but still the cost for replacement would probably be more than the part itself, and who knows what other parts may be needed. Or drive till failure? Tough call for sure.

 

Thanks, that helps explain the reasoning. I know they have a policy against people providing their own parts, too.

 

How many miles and what's the transmission fluid change history look like?

 

We are a bit over 80k. I believe the fluid was changed within the past two years. We've owned it for 4.

We also haul a trailer with it :\

 

not common on these, but it could happen.
usual 3 drain and fills and software update sorts most people out.
3rd gear pressure switches going bad, appear to becoming common on these.

if I was to take a WAG your VCM is still active, and motor mounts are tired and have lots of play.

 

Thanks, looks like I've got some googling to do!