I'm currently servicing my dear wife's watch. A tiny 30's gold watch. the escapement wheel has passed away. I can't find the reference. 1126 is written under the balance wheel but that makes no sens to me...
it's only about 1,5 cm long.
Here's a pic.
I think it’s a Cal. T12.6 – the ‘T’ is for ‘Tonneau’, the shape. So the movement is 12.6 mm wide and 21.9 mm long. They started life in 1934.
So the ‘1126’ you reported will be ‘T12.6’