Quick update on the o-ring question. I did not find the correct o-ring...yet. Getting to the dealer with the fitting and o-ring in hand was not going to work at the time, so I employed the suggestions given here to see if the very slow leak would stop. It did not.
So, I could've either bought the entire hose or just the female end quick connect. I opted for the just the quick connect fitting. The original was hard to get off since I don't have a bench vise but finally was able to get the old one off and the new one in place.
Success! I used the backhoe today and no leaks. What a pleasure.
Just a few more little things to address and all will be well.
When I make the next trip to the dealer, I will take the old fitting to buy some 0-rings to have in hand, just in the event they are needed. Plus, it would be good to have the part #.
Thanks for the good help! Another pleasure.
Tractor Gal