It all depends on how far back you want to go, but I would suggest:
Webley Mk.III
BSA Airsporter
Weihrauch HW35E
Weihrauch HW80
I would be tempted to list many more Webleys, but as they are not everyones choice I have listed a few of what I would term, 'The Classics'.
There are so many to choose from.