This paper toy is Gatling Pea, an upgrade available for purchase from Crazy Dave's Twiddydinkies and it is one of the first upgrade plants, based on the video game Plants vs. Zombies, the papercraft created by Blank Canvas. There are also Peashooter and Repeater Paper Toys at the site.
Gatling Pea upgrades the Repeater. It must be planted on top of the Repeater. It fires twice as fast as the Repeater and four times as fast as the Peashooter. The seed packet costs $5,000, the same price as the Twin Sunflower. It is also one of the first two upgrade plants you can purchase, after beating level 3-4. It does the same damage per Pea, but it shoots four of them at a time.
You can download the paper toy template here: Plants Vs. Zombies - Gatling Pea Free Paper Toy Download