To the best of my knowledge, HM prison, Wandsworth, nominal register of admissions are held at LMA. They are ACC/3444/PR/01 I had a look at them last year but I was looking for the dates 1890-1891 which were found in 046-050.
Like you, Pauly, I found a rellie in there on the census so from these LMA records I got the court where he was tried, the crime (stealing a knife worth 2/6) his sentence, age, height, religion, where born.
jane