SEAT CUSHIONS? Beware.
Kay Pam, regarding seat cushions. If you are sitting on a squashy soft cushion it can be dangerous. It may compress under you in unusual attitudes of the aircraft and even make it not possible to reach the controls!
They do sell expensive non compressible cushions, however we have found if you wrap a stack of NEWSPAPERS in plastic tape, to a comfortable fit for yourself or if a lot of people use the aircraft, several cushions of different thickness....and sew a nice cover over the package, you have created a zero cost NON COMPRESSIBLE CUSHION. Even if you stand on it it will not change shape.