At the behest of various Amstrad users, we have now made some new replacement keyboard membranes for the CPC664 - see
http://www.sellmyretro.com/offer/details/*BRAND_NEW*_Amstrad_CPC664_Keyboard_Membranes-2584
http://www.sellmyretro.com/offer/details/*BRAND_NEW*_Amstrad_CPC664_Keyboard_Membranes-2584