If you are with ATMS or AAMT you can buy receipt books on Scolina If you are taking payments through a Square or other similar 'plug ins'
Personally, I send my receipts via email through my booking system, that way people can't lose them.
You could do a similar thing by using this receipt-template I've created. Just remember to transfer it into a PDF before you send it so that it cannot be altered and to save a copy somewhere for yourself too.
If you have a hi-caps terminal I would suggest investing in a printer to print your receipts and staple the hi-caps receipt to it for your client.