In his initial rise and even thru his heyday Elvis bought many of his clothes from Lanksy's, a Beale Street Memphis clothing store which primarily catered to black musicians.
http://www.elvis.com.au/presley/the_king_and_i_bernard_lansky.shtml#sthash.vArdhTag.dpbsThe Elvis pompadour was also a copy of the black process which itself was a copy of white hairstyles. So there has always been sharing and copying, credited or uncredited, from respect or envy.
To his credit, Elvis was quite open about his musical, performance and sartorial influences. And this wasn't missed by the White Citizen's Councils, who attacked Elvis and rock-n-roll in language that's not too dissimilar to what we hear today.