I had the same problem with the black paint 'crazed' and it was also peeled away around the outer edge. So I decided to see what I could do, because I wasn't finding anything that looked remotely like it, and $100 after shipping is a lot, for where Rosie is in her rehabilitation.
OilGauge.jpg
I recreated the dial on the computer and printed out a new 'face' and placed it directly over the old one. I was having a time wrestling with the color settings of my printer to match the orange, so in the end I just printed the black part onto a piece of orange construction paper that I had in the house (kids finally pay off!) that was actually a pretty good match. And since it is paper, I hit it with fixative spray on both sides to knock down the water absorption (hopefully). Daytime, you can't tell the difference (yet).
oilDay.jpg
Nighttime is a different story, where it is pretty muted except for where the paint was already coming off the dial. I'll live with this for a while and see if any other ways to improve it spring up in the meantime. And fallback is always just get a new one

.
oilNight.jpg
If anyone else wants to try their luck with this too, here are the files. FYI, the background is overprinted and you can cut down to size. The scale is probably off too depending on your printer. I've got little key marks in there for where the screws go into the face, or you could use anything else for a reference, to measure and scale down your print appropriately. Once scaled and cut to size, to fit it on your face plate, I cut a hole about the diameter of a fat pencil where the needle pivot is, and then a slit from the hole to the nearest outside edge. That enables you to work it around the needle, without having take it off. Then with it in place how you want it, I rubbed on the paper over the screw points to find exactly where they were, took the paper back off and then cut tiny holes for the screws. Then I placed it on, one screw at a time, so that there was always one screw remaining in the dial face to keep everything in place. Good luck!
With Orange
https://i.imgur.com/Ny6kUMa.pngJust Black
https://i.imgur.com/8nmmzTa.png
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