The first go-round of the Montego was a replacement of the Mercury Comet. It was a twin of the Ford Torino for some time, and it would eventually be replaced by the Mercury Cougar when it changed platforms. From 1968 to 1971, the Mercury Cyclone was a high performance version of this car.
The newer Montego featured a 203 horsepower Duratec V6 engine paired with a 6 speed automatic transmission. There was also an optional CVT transmission and optional all wheel drive to replace the standard front wheel drive. With a retail price of $25,000, this was the lower end of the upscale cars. Nearly 65,000 of them were sold in its 3 year run.
The name of this car will be discontinued, but the car itself isn't going anywhere. The Montego becomes the Mercury Sable, while the Ford Five Hundred will become the Taurus. Both names were used on Fords and Mercurys in the past couple decades and were very successful.
These cars are already showing up on the used car market. You can find them in a variety of places, but for the best deals on cheap used cars I suggest checking out eBay.