For that grade at Gunks, aliens from green to purple, camalots from 1 inch (old red) to 4 inches, maybe double up on the two inch, will work nicely. Purple alien matches 1 inch camalot but is narrower and sometimes fits where camalot doesn't. (The old 4 inch cam will not fit the off-width at the top of Boston.)
There are times where a pink or red tricam is perfect. But you can climb a lot of climbs without even looking at them. Passively they can sometimes fit nicely and better than stoppers. Actively requires considerable care. They really must not wiggle after you set them, although I have seen one fixed tricam that wiggles quite dramatically
Avoid TCUs at the Gunks. Some very good climbers use them, though.
Buy at Rock and Snow (tell them what grades you are looking at). They are experts, know the crag, and will match any legitimate offer you might find in a catalog or on the net.
Enjoy whatever you choose.