1. I don't think you will ever find a really close match on the paint. That is debateable, it depends on how close of a match you are looking for.

2. Fixing it won't be that big of a deal. You can purchase paint stripper from Aircraft Spruce & Supply to get the paint off safely. DISCLAIMER- do try it on a small area to verify that there are no adverse reactions. (but there shouldn't be)

If it where me, I would strip the entire bottom half of the wing, it will be far less noticeable even with a different colour of paint. As far as putting the letters back, use liquid mask for the lettering. It will make a much cleaner line with no chance of bleeding if applied correctly. Also, if your cub has a flat or semi flat looking finnish (I'm assuming it does) you can spray 1 coat of clear flat over the entire bottom. This will accomplish two things, it will lessen the edge of the paint on the lettering & if your matching paint is gloss, it will no longer matter. I have used the Lustercote clear flat, it works great, just don't put it on too heavy.

Good luck, when you get it fixed post a pic!

Mike