I know this is late but I saw this searching for a recipe. I know what you mean about craving that duck. I love it.
Well hopefully I have good news for you.
I would get it at a small very inexpensive restaurant in San Francisco. The Hong Kong Restaurant. On Church street and Market.
I moved there in the early 80’s and would eat it as the mood would hit me. Then it disapeared from the menu. I finally inquired about it about 2000 (the year). The head waiter told me he lost his chef that made it. Then he called me one day and let me know he had a new chef so it was not on the menu but he would make it about 2 times a month and let me know so I could let him know how many orders I wanted. Hows that for service? It was as good as ever.No other customers got it. I felt so special.
So give the Hong Kong a call and see if they still can make a special order for you. I would get 2 or 3 and freeze them so I could have it whenever.
If you do contact them please tell them The guy who used to order the duck "says Hi from Palm Springs". They are some of the nicest people you will ever meet.
There food is wonderful and you can get a whole meal for $5.00. Every thing on the menu is delicious. I almost lived there literally, atleast twice a week for 20 years.
I recommend Tomato-beef chowmein. Trust me you’ll love it.
I scoured this entire valley looking for a restaurant here with no luck. But I came across a recipe for it someone scribbled on a post-it in 1981 from his mother. I could never make sense of it until I started to make it. It was great!!! I have been craving that for 5 years.
I better shut up here.
I hope you get this and it is some help.