Well, one of the things I'm quite enthusiastic about are image stabilizing binoculars, but they're way outside the 20-40 dollar
price range. They make it possible to read
boat names at a distance, or hold the aid to
navigation still so you can tell what it means for you to do.
In that range, you're sort of looking at small luxury items, like nautical paper napkins.
There are many old books, but you're going to be (hopefully) in a giant
catamaran, and the old books are good about
weather, but the tactics will be different for you than for their monohulls.
My Jim has always carried a pocket knife --you never know when you'll want to cut something; and for years, I did, too, a Swiss Army knife that included screwdriver and corkscrew. Still over your
budget, though.
Wait for someone with more apposite
advice.
Ann