It’s not even remotely true. Not only could you buy cannons, but grenades, mortars, etc...
When the Colonies needed a Navy, they hired Privateers who were already FULLY and PRIVATELY armed to bolster the ship numbers until they could get some ships built of their own.
Actually back then every family had a gun or 3...Mama took hers out to the well and to milk the cow...and was ready to shoot any man who came threatening to take away her long gun...
Thanks for the verification, I knew it didn’t sound right. These idiots just make things up and the reporters Let It Go by.