All I could find, at least so far, is this photo of his group, Vietnam Veterans Against the War (VVAW), (supposedly) meeting with the North Vietnamese communists in Paris. I enlarged and copied it to my TinyPic photo account. A link to the source is included.
Caption: "First peace meeting between VVAW and the NLF, Paris, 1971."
Below: photo as it appeared at source:
John Kerry, in sworn testimony before the Senate in April 1971, said he met with the North Vietnamese and Vietcong delegations in Paris in May 1970. He said they discussed their peace proposals especially the eight points of Madam Binh. Kerry strongly recommended that the Senate accept those proposals.
"I have been to Paris. I have talked with both delegations at the peace talks, that is to say the Democratic Republic of Vietnam and the Provisional Revolutionary Government and of all eight of Madam Binh's points...
...I realize that even my visits in Paris, precedents had been set by Senator McCarthy and others, in a sense are on the borderline of private individuals negotiating, et cetera.
Lots more at link:
http://www.americanthinker.com/2004/08/did_navy_lt_kerry_violate_the.html