The photo on the left shows Rivera with the Arkansas Travelers, though it does not depict his face very clearly. It is from the Shreveport Times of July 27, 1968. The photo on the right is from a website which communicates only in Spanish. I think the website is saying that Rivera has been honored by being elected to the Gallery of the Immortals of Sport in Ponce, Puerto Rico. His uniform seems to be that of the Ponce Lions (Leones).
https://www.baseball-reference.com/r...d=rivera001enr
P.S. Found an improved photo of him with the Arkansas Travelers. It's from the Arkansas Gazette of April 18, 1966, and is added below.