Jeff,
OSO member Kevin Schulte owns
www.hardlineproducts.com for a COTS product.
However, if you are going with vinyl stick on numbers for that beautiful boat, you are probably best visiting a local sign/vinyl shop, and having them whip up something custom for you. It should only take an afternoon to do; depending on how busy they are.
As mentioned above, they don't call Ryan Beckly 'Stickerboy' for nothing. He does great work.
If you get in a pinch, call Pat. He has a vinyl cutter in his office.