Okumarts Games has some more retro-space printable miniatures now available. You can find them on RPGNow.
From the release:
Okumarts Games Retro Space Set Four: Space Hero Squad gives you twelve original 30mm Pulp/Retro Sci Fi themed miniature figures perfect for roleplaying games or wargames. All files are 300dpi and include front and back views. This is a layered PDF giving you Five options of colours. There is also a super secret layer full of awesome bonus content! Don’t miss it!
Cardstock Miniatures are an affordable and attractive alternative to metal or plastic miniatures. Print as many as you like as often as you like.
You will need a colour printer, cutting tools, glue, foamcore and time. Assembly instructions are included.