I've been hand pumping for over 20 years. I've owned several pumps and my latest is an Air Venturi Hill mk4 or 5. I can never remember. I've been using it for the last 4 years and I've only replaced one o-ring.
Like you, I do it for the exercise and my reward is shooting. That works for me.
Like you, I do it for the exercise and my reward is shooting. That works for me.