The ammo situation is the kicker.
Without that I'd get a relatively cheap Lee-Enfield (any model but my preference is No1 Mk3's) that was sporterized at some point, cut the barrel to 16"-20" and run that bolt! I'd still do that if I found some .303 ammo.
In todays market I'd get an older used .22 LR bolt gun and run that bolt... unless .223 was a "destination" caliber for me, ie it will do all I need out of a bolt gun. Then I'd go .223, my needs are heavier but I really like having .22's in my real "work gun" type actions.
I have a Ruger No. 1 in 45-70 and there's a lot of entertainment value in drilling fast(er) reloads with falling block single shots.