i just realised you can't buy the keyboard anymore! great job apple

found on amazon https://www.amazon.com/Apple-Smart-Keyboard-12-9-inch-Generation/dp/B07P9VLBPS

and one on trademe for more https://www.trademe.co.nz/computers/tablets-ebook-readers/ipad-accessories/cases-bags-protectors/listing-2438063196.htm?rsqid=0cc9323c388a43b2b60c54dc3b2d7d0a-003

essentially anything that uses the smart connector but as i said as far as i'm aware there was only 2 and they're not cheap.

I thought I replied but it's either lagging or I'm losing my mind. 

In terms of a second hand iPad - even if it is in good condition, wouldn't two years of charging have some effect on the battery life?

apple says ipad battery is twice better than iphone. so in theory no. but you can ask them to show a photo of the battery status. that's a good point. my ipad 1 after 10 years still get the same use time i had the day i bought it. but then i don't use it very much.