Seamaster 120 Lady: improve or change movement?

Hello all,


my wife owns this beautiful Seamaster 120. I think the movement is a caliber 681 that got reworked a year ago. However, she is constantly having trouble meaning that it tends to run far too fast. This is getting a bit more under control after demagnetizing but just for a few days.


I am now thinking: is there any possibility to make this movement more robust? Or as the last resort: is a more up to date movement fitting to that case perhaps?


Best regards from Berlin, Germany

Torben

Here a picture of the watch: