Where I can look for an 'older' pony who would be happy to just go for occasional quiet hacks and enjoy being fussed and looked after the rest of the time?
Try Blue Cross and RSPCA too as they have loads of "happy hackers" that just want the quiet life. Blue cross in particular let you have the horse and then pay for all its vets bills!
It looks like I'm too far from those charity places and they state that you have to visit a few times to match you up with the right horse. Anywhere outside Cornwall and I'd be lost!
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Anything from 13.2h to 15hh would be fine as I'm only light.