Answer: Red Valentine rhubarb is listed in the current catalog from Boyers. http://www.boyernurseries.com/index.htm
An internet search using a search enging such as google and red valentine rhubarb as the search terms should bring up additional sources. Your local nurseries and garden centers may also carry it in stock. Finally, the following compendium of sources might yield something for you, although I do not know how up to date it is.
Good luck with your search.
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