I can just imagine the face
@t-tony has just pulled...
Plenty of refurbished XP laptops available for a 100 notes on ebay which will be fine, most of them will be ex-corporate high end kit so perfect for the job. But for the love of all things sacred don't start using it to browse the internet or you'll be quickly overwhelmed with eastern block brides and enhancement creams (before you get excited, they will all be cons and you will end up with neither).
No support or updates from MS anymore, and because a lot of corporates and banks still use it widely then it's still a big target for malicious activity. If you need to put stuff on it download it to a secure machine which is updated and runs AV, then copy it on to a memory stick to transfer. Then burn the memory stick after it's been in the XP machine.