Airfix

Airfix 1/72 scale Space kits listing:
Airfix is probably the best know manufacturer, in their own words:

Airfix is the oldest UK manufacturer of scale plastic model kits and has been producing kits for the mass market since 1952. Airfix produce a wide range of kits aimed at all types of scale modellers with subjects such as; military aircraft, ships, cars, dioramas and military vehicles.