My advise to you would be to NOT PAINT it at all. It is worth more the way it is. Believe it or not, their is a big market for old lures. Look around and you may find it is worth some cash. Or it maybe worth more not to paint it and work a lot better for catching fish if it has no real value.

You'd probably want to use enamels.

http://www.riskreactor.com/Industries_Served/Fishing.htm I found this website which sells fluorescent paint for painting lures. I also saw a website showing old lures that supposedly sold for lots of $$$ , like in the thousands of dollars, so the first poster here might be right... is it an antique? Anyway good luck. If I were impatient I'd just find a bright shade of nail polish, (bright yellow?) cheap, easy and quick.