I have an 'as new' Bora identical to Paddy's currently for sale...
interestingly mine has open sights.
Air Arms/Sussex Armoury made foresights to fit all barrel designs over the years, so I would be surprised if there are not versions of most sidelevers with open sights kicking around - a lot of dealers special ordered what they wanted and the Sussex armoury sidelevers were resurrected by others as well as air arms ......I will try and dig out some adverts I have somewhere.
"But we have our own dream and our own task. We are with Europe, but not of it. We are linked, but not comprised. We are interested and associated, but not absorbed."
Winston Churchill 1930