We've just wrapped on a segment for NOVA which explores the future of space suit design.
Mickey Mouse's helmet would not be enough to prevent his ears and arms from depressurizing and turning into ooze. Unless this dungarees and shirt are fitted with cutting edge zero gravity design his whole body would quickly melt in space.
Not a pretty picture to put on your space thermos.
Best to stick with the standard Mickey Mouse dishwear if you want to be safe.
Or you can go with the classic black and white.