I am trying to think of a budget friendly wedding gift for my cousin and his wife. They got married last summer but we didnt attend and i was too busy/crazy to get to it. My mom is now pushing me to get something. This is not a close relative but family politics is dictating sending something, and their registry was pretty cleaned out. I am stumped!

Ideally i would like something:
-under $50
-not too hard to ship
-not too huge (they are in nyc)
Thanks in advance!