Update: It really does go without saying, the FX-CG50 is a beast of a calculator. But my trusty FX-991EX is still good for a lot of things. They are both good calculators. :
OS & Files - Casio Calculators
Casio FX-CG50 Calculator, Hobbies & Toys, Stationery & Craft, Stationery & School Supplies on Carousell
Calculator Emulators & Software | CASIO Education Australia
Update Your CG50 Operating System. Now Includes Python! (OS update) - YouTube
CASIO PRIZM FX-CG50 Color Graphing Calculator – The Gadget Collective
Casio FX-CG50 Calcuso Calculator with Case : Amazon.co.uk: Stationery & Office Supplies
Graphing Calculator (for A Level) fx-CG50, Mobile Phones & Gadgets, Other Gadgets on Carousell
CASIO FX-CG50 Graphic Calculator | WHSmith
Eddie's Math and Calculator Blog: Casio fx-CG 10, fx-CG 20, fx-CG 50 Update to Software Version 3.1