Multiple keyboards layout with only 2 layouts on Shift alt ?

I usually write in both English and Hebrew, however from time to time I need to type Greek letters or letters from other language (but not very often).

So the the setup I want is Shift - Alt swaps from English to Hebrew only, but When I press the keyboard applet I can choose which layout the I want from a list.

I am using Ubuntu Mate Raspberry build.

Can I achieve such setup?