I went through this exact same scenario about a year ago. My clip broke exactly the same way as yours did and I embarked on this same mission. After lengthy amounts of research time online, I ended up buying 3-4 different replacements online from different vendors and all of them ended up being the smaller size. In fact, they even have the smaller size on the shelf at my local O'Reilly's. However, the larger clip was nowhere to be found anywhere.
I researched the exact hose online at fordparts.com (matched to my VIN for my 2005 van) and then went down to my local dealership with broken clip in hand. When I got there and showed the parts counter guy my broken clip he knew exactly what it was. He said that they used to have a small bin of clips there for the dealer mechanics to use, but that they were all gone and he said he was unable to ever get any more in. He said that the last couple of times they needed one, they had to order the entire line because it comes with the clips. I said that was pretty ridiculous for a $.50 clip and he agreed but said that he had no other options.
Still in disbelief that they wanted me to spend $35 on a new line for a $.50 clip, I went to another dealership just to hear the same answer. Both parts guys agreed that it was really stupid, but they offered no alternatives and I certainly never came across the bigger size clip anywhere online. So I bit the bullet and just ordered a whole new line which included the clips.
Sorry this doesn't really help you out, but I certainly feel your pain. I guess if I had a 3D printer maybe I could have just made a few replacements, but I don't. If you do happen to find a source for just the clip and it's actually the right size, please post back here with the details. Good luck.
