The lab in question, Dwayne's Photography, is still in business, but stopped accepting rolls of Kodachrome on December 30, 2010, citing Kodak's discontinuation of the necessary developing chemicals.
Based on The New York Times article by A.G. Sulzberger, "For Kodachrome Fans, Road Ends at Photo Lab in Kansas," originally published December 29, 2010.
The camera that Ben (Ed Harris) uses is a Leica M4-P, a rangefinder camera built from 1980 to 1986. As cutting cost strategy this is one of several Leica models manufactured mostly in Midland, Canada, instead of the legendary Leica factory in Wetzlar, Germany.
KODAK produced many types of film over its history. Kodachrome was the first color transparency (slide) film, and it differed from Ektachrome color transparency and from the color negative films that are used to create color prints. Kodachrome had no color dyes in the film itself; instead these were added during the development process, making Kodachrome processing very different from all other films produced by any other manufacturer or by Kodak itself. It's actually still possible to have Kodachrome developed, but because the film doesn't contain color dyes and the dyes are no longer manufactured any processing of the film these days results in black and white images.
Kodachrome was originally manufactured in Rochester, NY... Home Kodak.