The best print of "Black Camel" comes from a gentleman who posts as "Johnny Dollar" on the charliechan.net and mysterymovies.com message boards. However, he has not posted in a very long time so I'm not sure if he still offers it. I bought mine from him for $15. Mr. Dollar had the great wisdom to tape this movie when it showed on AMC in the 1980s. That print is miles better than some of the 16mm dubs floating around the grey market. His e-mail is david at rediscovery dot us. It might be worth an e-mail to see if he still offers it. He is not a grey marketer by trade so it's possible he no longer does.
I suspect Dennis Harmon uses Mr. Dollar's DVD as his source so I would second Rush's suggestion to check him out as well. I just ordered "Broadway" and "Shangahi" (two films which I don't have the restored versions) from him and they should be here later in the week.