… is from pages 603-604 of volume 2 of The Collected Works of Armen A. Alchian  (2006); specifically, it’s from Alchian’s 1977 essay “Economic Laws and Political Legislation” (original emphasis):
History reveals a contest among people of differing relative talents and modes of competition. The politically adept, who may say they prefer capitalism and indeed do, will nevertheless seek greater government authority…. Businessmen who think they would be good politicians advocate greater political authority – out of self-serving interest rather than ideology. We who are good at political power acquisition will exploit and extoll it without necessarily being for socialism per se nor advocating political power because we happen to believe political power is a better way to order society. Instead, it permits us to better achieve enhanced status.