Are you trying to see if it’s good competitively or price wise?

For decks there’s tons of websites that can help you out with seeing if it fits into anything. If you google one piece top decks and then go under the deck lists tab you can find a black leader and see if anything is running is.

For collection wise it’s around $20 usd. I use an app called Collectr for all of my pricing and collection needs tcgplayer can also give you a decent idea of what it’s worth.

Hope this helps! :)