The Stargate itself is made from 9 modular units designed by the Ancients Jason Ku. The ramp is modified from Jason's design. Diagrams for the Stargate are on Jason's site.
The guy walking out of the Stargate is modified from the frog base. He's not a pirate; that's a 'zat in his hand.
Too much information: My wife and I saw the movie Stargate on our first date. We talked through the whole thing, but I thought the movie was kinda goofy. However, we are now completely hooked on Stargate SG-1.
Go MacGyver.