Dave Graffam Models has a whole series of cobblestone streets available up on Wargame Vault.
From the page:
This large printable map features cobbled roads in an irregular pattern inspired by real cities. The details are sharp, and it’s designed to be the perfect complement to my collection of paper models, giving you a beautiful surface for building your own bustling town or ruined village. It’s easy to print in one piece at your local shop, or in sections on your desktop printer. An optional 1-inch grid is included.