I believe the model you are showing is in the same date range (mid to late 40's) as the above.
Pushers should be the large mushroom type pushers. The ones that you show are much later. Unfortunately, they are impossible to find and not a great design so once they break, you either fix them or replace them. That is a problem in its own right as thread diameter is larger than standard 2.75mm and tube is 4.5mm so there are really very few choices you are left with! I have had some success making these, but process is long and 100% accuracy is paramount ... Here are some failures !
View attachment 217958
have a look at the following thread ...
https://omegaforums.net/threads/universal-chronograph-pusher-variants.10468/ Click to expand...