When searching, note that various spellings are used: seperator, separator.
Gustaf de Laval, a Swedish engineer who also made contributions to the design of steam turbines, developed the first centrifugal cream separator. Infoplease has a description of how deLaval centrifugal separators work. He founded a company that continues to produce separators. The original company was AB Separator which became Alfa Laval AB in 1963. Tetra Pak acquired Alfan Laval AB in 1991. In 2000, there was a change in ownership and structure that resulted in two independent companys: DeLaval (milk production, focused on the farm, not not subsequent processing) and Alfa Laval (separation, filtration, fluid handling, heat transfer).
brochure with a description of how disc stack centrifuges work.
Lakshmi cream separators (manufactured by CHADHAELECTRO IND.) are available from Homestead Products.
There appears to be a Plava brand cream separator made in Russia.
Early 20th century cream separator: DeLaval.
A site put together by a couple who have collected antique milk-related products including cream separators, churns, milk bottles and other items: Doug & Linda's Dairy Antique Site
Here is a company that makes new cream separators out of plastic for about $300: Novo Cream Separators