No glass ones, but there are filters from other companies made of resin with less colour cast than a Lee Big Stopper.
I knew only of the Hitech ND 10 stop filter that has an even worse color cast. Which other companies make the 4x4 10 stop filters?
5D3, 6D, 600D, RX100
16-35L, 24-70L II, 70-200L II, 100-400L, 50L, 85L II, 135L, 24TSE, 40, 100 macro, 18-55 II, 55-250 II, 600RT x 4
I come here to learn something new, not to learn how bad my gear is - I know that already ;-)!