Perfect wrote on Trade Me: "Earl was my buddy and was executed many years ago and I kept our letters and pics that he sent from a phone a prison guard smuggled in for him.
"He was such a wonderful man and spent damn near two decades on death row for his crimes.
"A self confessed ex-biker and hard man who made some bad drug-induced decisions. It breaks my heart to finally have to do this."
Perfect said he was supposed to get Lynd's ashes "as per his wishes" but "his girlfriend can't bring herself to part with them".
The pair became pen pals after Perfect read a book about death row inmates and contacted an American-based group that offered support to condemned inmates.
He said he had received more than 100 letters from Lynd, who had been upfront and honest about his offending, leading up to his execution.
He described reaction on Trade Me to his posting as "mild, which is quite surprising. I thought they may have ... polarised opinions."
By last night two people had bid for the items, with a top offer of $21.
A Trade Me spokesman said the advert had not been withdrawn because no complaints had been received about it.