Source for 2 x 2 exotic turning squares.

I am looking for exotic turning squares that measure at least 2 1/8 x

2 1/8 x 9" long to make Kaleidoscopes. The finished Kaleidoscopes are 2" in diameter and i was only able to find squares listed as 2 x 2 so i ordered a bunch from a mail order house but all measure 1 7/8 x 1 7/8 so now i am looking for a source that sell larger squares.

Any assistance will be greatly appreciated.

Dave