This gundam paper model is a SD FA-78-1 Gundam Full Armor Type (aka Full Armor Gundam), a Mobile Suit and variant of the RX-78-2 Gundam equipped with external armor, featured in the original design series Mobile Suit Variation, the papercraft is created by [unknown]. There is also a very detailed FA-78-1 Gundam Light-Type Paper Model on the site available.
The new weaponry of the Gundam Full Armor Type consists of a large rocket-firing cannon mounted over the Full Armor Gundam's right shoulder, four missile launchers, two mounted in the upper torso and two more in the knees, and a new twin-barreled beam gun secured to the right arm. The Gundam Full Armor Type also had several removable armor modules that could be placed over the Gundam's existing armor. These new armor modules also incorporated several additional thrusters and maneuvering verniers. [Source: wikia]
You can download this gundam papercraft here [Note: No Instruction!!!]: SD FA-78-1 Gundam Full Armor Type Free Papercraft Download [Box] [Gavitex]