You want to avoid paying shipping?

CLC might sell some but they're not local.

I've sourced 1088-spec from Boulter up in Bedford MA, near Boston. 

What sailing canoe (plans? designer?) you got in mind?

when i lived in NYC area, i just drove down to annapolis/CLC to pick up my plywood.  i don't recall any local sources and i don't think that situation has changed.

that said, you can do a google search, make some calls, and see what you can find.

h   

   Try ML Condon in White Plains.

   Yes, Condon's is the place to go. I just bought some there recently.

Dan

   Yes, I know M.L. Condon's in White Plains. They're less than 10 miles from my home. But I'm looking for 4mm ply and they're out and won't special order is my understanding.
Thinking of building Selway-Fishers Artic Skua. 

General Woodcraft in New London, CT may have what you need.  It is closer than Md or Mass.  https://www.generalwoodcraftinc.com/marine-plywood-and-hardwood