If he's ok with having 2 switchable banks/slots instead of 4 my KS Masters might be a good replacementSomething like this?
Thread 'KS MASTER - USB Programmable ROM with Auto-Switch/KickSwitch (1MB)' https://www.amibay.com/threads/ks-m...-rom-with-auto-switch-kickswitch-1mb.2447021/