Is there any keyboard shortcut to turn on and off shuffle and turn on repeating on iTunes?
find repeat and shuffle in iTunes menus and memorize their name as is.
Press CommandSpace, Type Keyboard and press enter.
select Keyboard Shortcuts
in left side of the page, find Application Shortcuts and select it.
click + button below
in front of Application, choose iTunes
type the exact name of the menu item for shuffle and repeat 
set shortcut keys for them.