I bought this printhead by mistake from Misco, I opened it before I realised its a 5 head printhead and not the 4. Never been in a printer or had ink near it.
The box says CN642A and here is a link to the amazon page with the compat printers.
Amazon.com: 564 PRINTHEAD - CB326-30002 CN642A For use in HP 564 Photosmart Printers: Electronics
Cost £40 but would prefer just to swap for inks if possible. PM me if you have anythign going spare.