One thing that occurred to me when talking to someone rolling in to NY on the tail end of a crossing...
Try to get on contact with corporate headquarters of various nationwide chains and try to get them to give you letters from corporate that you can laminate and carry and which will get you special "take the bike in inside and have someone watch it for you" service on your solo tour. Even with a lock, having a bike loaded with gear is not something you want to leave outside, yet you will need to go inside regularly to buy supplies.
Walmart, Target, REI... any chain that you can hit up regularly for supplies.