Audiophile Grade RCA Input Suggestions?

Have you looked in Parts Connexion?

Some of the best is Cardas, and also some of the hardest to use> :)

And just a heads up, the Cardas ones won't fit the Dino PCB, as it has doubled-up ground and signal pins. The two-way terminal component used on this board has 3 prongs only (L, R, and a shared G).

Good suggestions on Parts Connexion! Unfortunately they don't have any two-way RCA inputs. 

Also, the input component needs front-facing screw holes like the originals, as the back of the chassis is secured by screws that go into the component. 

This image shows what they basically look like:
https://images-na.ssl-images-amazon.com/images/I/61hyXJZcoTL._AC_SL1100_.jpg

Here are the cheap-o versions that would work, and be equivalent to the Trichord ones. 

https://www.amazon.com/uxcell-Position-Stereo-Female-Connector/dp/B013SYV9S6

Check out Parts Express!
https://www.parts-express.com/?utm_group={group}&msclkid=fe609a3cbab01e515a18c5e768664735&ut...

Audio Note or Cardas.I think Audio Note is the best.

Cardas does not make a two-way RCA component with 3 leads. Theirs are doubled up, as each signal path and ground connection has its own lead (a better design than what I’m looking for, but won’t fit into the printed circuit board I’m working on.)

Parts Express was also a no-go. 
Also, if anyone missed it, see my link above for an example of the specific form factor I need. 

If you're looking for a 2-RCA jack component with 3 leads onto the circuit board, you are not going to be able to get anything good.  Best bet is to search through digikey's offerings:

https://www.digikey.com/en/products/filter/barrel-audio-connectors/434?s=N4IgjCBcoEwBxVAYygMwIYBsDOB...

If you're willing to solder chassis wire between the RCA and the board, the Cardas are excellent value.  They are the "poor man's Furutech Rhodium" components.  If you want the best, get Furutech Rhodium.  They have an extra heavy plating of rhodium on their stuff.

I put the link to inspire you to get the OEM part.
It's likely a custom run.

I agree that I think you're stuck with stock if you're not willing to build your own solution with more standard connectors. I've liked the WBT low mass RCAs I bought while switching everything I could over to pure silver, but haven't found the influence to be huge. Based on my modding experience, I'd spend on good film & foil caps, a power cord, or solid core silver internal wiring before upgrading RCAs. 

How can you tell if it is just the RCA connectors that seems to be shorted and not actually in the electronics passed the connector itself?

Doug,

I used a multimeter across the ground and signal connections on the input component to verify that there is an internal short. 

I performed the test out of circuit as well, to make sure no other parts of the circuit were messing with my reading 

I also compared the reading to the functional RCA jack to verify what the readings should be. 

I would probably just install normal style RCAs and wire them to the PCB.  I have been eying these up:
https://www.partsconnexion.com/KLEI-86828.html

Thanks for the suggestions, all!

I dropped in the cheap replacements, which really seem like the same OEM components that were in there. 

I also upgraded the opamp chips from SMS2019 to THAT1510, which turned out to be a very nice mod for the tightness and clarity of the bass.

SSM2019*