Hi again Johanne,
I've been looking on
Abebooks for various combinations of WW2 dates & newspaper titles and the prices do seem to vary wildly, mostly only a few quid but one or two more so.
Interesting article on newspaper collecting from the FT
here.
US
eBay buyers guide.
The search term "newspaper collector" (including quotes) gets a lot of hits on google, some seem relevant, particularly if the search is narrowed to 'UK'.
Good luck,
Adam.