Eco flex 30 is a platinum based silicone, it will not cure on op of a tin based silicone (as well as a long list of other things including latex). Odds are good that they painted the mask with tin based silicone since it will cure on top of plat silicone. you should be able to paint with tin based silicone no problem.
Tin based silicone is in tubes of silicone caulking, as well as tubes of silicone sealant both found at HD. Tint with silicone tint (make sure the so strong tint is meant for plat silicone, I use it for urethane foam and blood but never silicone) Oil paints can also be used to tint but they arent 100% a sure thing.