I agree with your comments on the 29a - its a magnificent watch
The only thing I would change would be having Made in England on the dial as opposed to Britain to take it a bit nearer to the original - a minor point however
I love the accuracy of the ETA2801-2 movement
Interesting suggestion re retrofitting an old British movement - not sure how many takers there would be though. If the price wasnt too high I would probably give it a go