I have back issues and can relate to you. What are the space requirements for a mating pair of peafowl? We are thinking of adding them to our one flock just to assist my disabled rooster.
My hubby is agreeing on peafowl after the guineas are gone. So next spring I will look for a pair. Keep asking him ya never know.
For free ranging space, they utilise all of our 5.5 acres when they want. If you want to keep them penned, I'm not sure what the dimensions would be but you would want it as tall as possible so they have room to fly/perch high/fan tails. The only things that I've had to learn on the fly (I did not plan to have peafowl - male showed up last year & adopted me) are that you have to feed them well, give them a sense of security & keep them penned for at least the first 3mos you have them so they log their coop as "home" & don't take off. Making them feel like they have a good home is important if you want them to stick around. They fly really well, they have no problems walking long distances & they can be very loud. Not just during mating season; they have a clown car honk/trill they use to call to each other or as an alarm when they're not happy.
Checking out the peafowl section here might be more helpful than I can be since I'm still learning.