The pink bellied snapper is just a color variant caused by selective (maybe lucky) breeding. Usually seen with Florida snappers, theres one on www.kingsnake.com in the classifieds right now. Very cool turtle. I wouldn't recommend any snapper unless you have room though. They get pretty big and are capable of removing digits. If you are set on getting one though buy a hatchling. Keep in mind mine grew from hatchling to 6 inches in less than a year. I think minimum recommended tank size is over 200 gallons for a common or florida and something like a thousand for alligator snappers. Don't get me wrong they are awesome turtles just know what you're getting into. let me know if you have any questions about their care, etc...
http://pets.webshots.com/photo/2635448800077251788LMTnPR
http://pets.webshots.com/photo/2351637710077251788fIrPXg
http://pets.webshots.com/photo/2635448800077251788LMTnPR
http://pets.webshots.com/photo/2351637710077251788fIrPXg