Only options you really have to run that rifle in the Quigley would be to replace the buckhorn barrel sight with a smith enterprise ladder sight. You'll have to be real good at kentucky windage to hold off target enough for spin and wind drift. Keep in mind the closest target at the Quigley is 3oo+ yards and it's shot offhand.
Other option would be to get a scope rail from Steve Earl and mount a DZ scope.
Probably in the end you'll be better off to get a dedicated bpcr rifle.
