The second one is a hs8 navigators watch from 1942 it was actually issued to the air fleet arm section of the Royal Navy if I remember right. They where used by navy pilots and navigators presumidly on air craft carriers?
They have chronometer rated movements a lot have very poor quality cases the metal reminds me a lot of dinky car metal.
There are a few s/s ones out there but I've never seen one in the flesh.
Price well I've just sold mine for £390 but I'd say anywhere up to £450 for a good one.
The first looks a bit Frankenstein to me? But I'm no expert.
Hope this helps.
Baden