I see no evidence that he actually said these things. I believe one of the principal sources for these quotations is this ad by Common Sense for Drug Policy, which ran in 2006. It claims to be a summary of the 1998 book Drug Crazy, but the bold quotations do not appear anywhere in that book.
The book From Bud to Brain: A Psychiatrist's View of Marijuana by Timmen L. Cermak (Cambridge University Press, 2020; p.203) identifies the "... as good as white men" quote as an urban legend.
However, the fact that these exact quotations were false shouldn't imply that they are an inaccurate summary of Anslinger's views. He believed all these things. Here is how he put it in a 1937 magazine article:
Those who first spread its use were musicians. They brought the habit northward with the surge of “hot” music demanding players of exceptional ability, especially in improvisation. Along the Mexican border and in southern seaport cities it had long been known that the drug has a strangely exhilarating effect upon the musical sensibilities. The musician who uses it finds that the musical beat seemingly comes to him quite slowly, thus allowing him to interpolate improvised notes with comparative ease. He does not realize that he is tapping the keys with a furious speed impossible for one in a normal state.
H. J. Anslinger with Courtney Ryley Cooper, "Marijuana, Assassin of Youth," The American Magazine, vol. 124, no. 1, July, 1937
One statement to Congress in 1949:
I think the traffic has increased in marihuana, and unfortunately particularly among the young people. We have been running into a lot of traffic among these jazz musicians, and I am not speaking about the good musicians, but the jazz type. In one place down here in North Carolina we arrested a whole orchestra, everybody in the orchestra. In Chicago we have arrested some rather prominent jazz musicians; and in New York.
Sloman, Reefer Madness (1998 [1979]), p.148, quoting Eighty-First Congressional Appropriations Committee Hearings
Anslinger was not joking about going after musicians he considered "not good"; for example, he stalked Billie Holiday for over two decades, successfully arresting her three times on drug charges. (Lauren Michele Jackson, White Negroes [2019], p.140)
He also said in 1956:
60 percent of drug addicts in the United States are Negroes. (ibid.)
And from his private notes:
Colored students at the Univ. of Minn, partying with female students (white) smoking and getting their sympathy with stories of racial persecution. Result pregnancy. (Sloman, Reefer Madness, p.75; a photo of this page in his notebook is included at the end of the book)