I must add that ofcourse some vintage target rifles like the mk3 and Osprey ST are getting more and more rare to buy
SSPs and other recoilless more modern guns are easy to find.
HW30;...dont know..they're great guns, had one, our gunclub has 2, but they dont strike me as vintage for bell target.
HW55 maybe if it has to be HW? Allthough also rare.
Old target rifles already have peeps fitted. Aftermarket fitting of peeps on rifles not originally made for peeps may give you adjustment issues.(height). Especially at short 6yrd range.