Your vet can help with the reissue as far as I know. I would imagine you would need pony's name as on passport, age, height, colour etc. Also, technically you should take the passport with you whenever you travel the pony anywhere. And I can't remember having once had to produce my ponies passports and they do camp, rallies, shows etc.
Defra has a comprehensive list of PIO 's currently authorised on their website , with about 18 that don't run a stud book but can issue passports . Is he a particular breed ? That might be a place to start . If its any use to you to try and narrow it down , one of mine has a pet iD one , and that's blue cover . The other one has no cover .
Last summer bought DD a pony advertised in localish paper, all good. Took it straight to pony club camp.Bit of a disaster DD massively overhorsed. Went home licked our wounds started again.We had taken Pony passport to camp. It had a red cover,don't remember many details. Expected it to turn up eventually. Forgot about it. Anyway....... After a lot of work, the pony is great,if a bit strong, our daughter just wasn't as prepared as 4 years of lessons would indicate! and we can face pony club again, but no passport.
Has anyone any suggestions what to do to get a replacement ie which PIO red book might be from. DEFRA no help.We don't have last owners name or tel.no. to ask them questions. we will just have to turn up but it's quite a distance, I'll feel an idiot and embarrassed that the pony has been challenging!