What dates to approx. 1969-1970.

For that period, the crowns would have been JL crowns. You can occasionally find them on eBay, but let me warn you, they're likely yo be at least $75/ea.

I think that's passable. It's definite the right era for late 1960s boxes.

To me, it looks like an American watch, with a refinished dial to make it look like a European one.

It might be cheaper to find a complete 815 or 825 movement than source the parts piecemeal. For example, clutch wheels (a rare part since they break all the time) are over $100 each when you can find them. I have a couple left but will only sell them in the context of a complete overhaul.

Sorry, no idea without a photo. Most citizens are not collectible.

1) Looks like a repair mark
2) No, 'virtual' storefront only.

Escape wheels are very tricky on these as there are variants. You're probably going to have to count the teeth.

What picture?

That's a hard part to find as almost all the watches left out there, have that part in a broken state.

It was sort of under engineered from day one.