It's called a Lookout Car seat, they sell them at Petedge or do a search and compare prices.
I think I paid around 60.00 after shipping for Pita's, she weighs right around 4 pounds and it fits her just perfect and I have a regular car, a Ford Fusion. They sell a bigger one for an SUV too. Try this link
http://www.petedge.com/sdx/H25596.jsp