Here are some pictures. As you can see, mine has the double handles. While it's not quite as handy to open as a single handle, there is really less to wear out (no rods and pins) and it's a lot more secure than a single.
As to cost, I am the second owner, but the original buyer paid $1250 installed (lights wired, foam around the perimeter, and four clamps). That was in 2007 though, so it's probably higher now. He used it on a work truck, so he was in and out of it daily. Other than a couple of holes in the screens, it's like new. I gave $400 for it used.
Good luck in your search.