Reference:
So you may find it easier to locate an ETA 2892 - A2 hour wheel.
No - that won't work. The hour wheel on an 1128 is completely different from the one on a 2892 A2.
The 1128 is a GMT movement and the hour hand can be advanced in one hour increments. This is done via the hour wheel, which is actually a double wheel that has a clicking mechanism inside to provide the one hour jumps. Over time this wears out, and the hour hand fails to advance after a time, even when you are using the normal hand setting position, like this:
[video]https://youtu.be/R2velHmYisI[/video]
I replace the hour wheel at every service because of this, since sometimes there is no warning that the wheel is about to fail.
User aalinamin - the hour wheel is not discontinued, however since Omega stopped supplying parts to third party resellers, many would be out of stock by now I suspect. There is no way to repair the wheel, so replacement is the only solution. You mentioned in the parts wanted thread that you need one that is 2.8 mm tall - there are several different heights and none are listed as 2.8, so the closest one is 2.74 mm, and that is part number 7221128310462. If you want me to confirm that is the correct wheel, let me know the specific model of the watch you are working on, and I can double check it on the Omega Extranet. If you don't know the model, I can look it up by the serial number also.
Cheers, Al