Walleye for Champlain and the lower portion of its tributaries goes from the first saturday in May to March 15th. So, you'll have to wait till May. They have to be 18" and you could keep 5.
Swanton River? Do you mean the Missisquoi River that flows through Swanton? If so, then Champlain regulation apply to 5120feet downstream of the Swanton Dam (Riverside Cemetery)