I wasn't riding when I lived in NYC, but I used to get dance and yoga clothes at Paragon on B'way, and I remember them having a good cycling section. I just looked at their website, and they seem to carry a lot of brands, so that may be a good place to try stuff on. I bought my BF some Sugoi tights there 10 years ago, and I wore them myself this winter, and they were still perfect.

Better not to skimp with shorts, the cheapo ones don't last, so you end up spending more in the long run. You'll probably need 2 pairs. If it's going to be hot, I'd opt for 1 short sleeve and 1 sleeveless jersey, either a bolero or armwarmers, and a long sleeve base layer just in case it gets chilly.

Where are you heading? I'm feeling jealous already.