Manual: MT260 OM CASIO EN : Free Download, Borrow, and Streaming : Internet Archive
Demo Casio MT 260 - YouTube
Amazon.com: BestCH DC 9V AC DC Adapter for Casio CASIOTONE MT-260 MT-540 CT-430 CT-102 CT-510 CT-370 Electronic Keyboard Piano 9VDC Power Supply Cord : Musical Instruments
9v Ac / Dc Adapter For Casio Casiotone Mt-35 Mt-36 Mt-140 Mt-260 Mt-500 Mt-520 Mt-540 Mt-820 Ct-102 Ct-430 Keyboard Synthesizer - Ac/dc Adapters - AliExpress
FITE ON 9V AC/DC Adapter for Casio CASIOTONE MT-260 MT-540 CT-430 CT-102 CT-510 CT-370 - Walmart.com
AC Adapter for Casio CASIOTONE MT-260 CT-430 CT-102 CT-510 Electronic Keyboard | eBay
Casio Tone Bank MT-260: My sister got this for Christmas in 1989... Used and abused all throughout our childhood and it still works wonders! : r/BuyItForLife
Casio MT-260 | Reverb
Casio Tone Bank MT-260 Vtg Electronic Keyboard Made in Japan Working in Box | eBay