I applaud you honesty in sharing this story with us. We all have said something stupid we later regretted. You did help the child by giving him money that I'm sure they needed. If you're motivated and time and chance allows, you may want to seek this child out again (if he's in your area), and do something nice for him (give him a toys r us gift card?). I have a very, very, very short list of people that I one day would like to apologize to for, for something I've done in the past. A year ago, I was able to make one apology, and it lifted a lot of burden off of me. Hope this advice helps
On another note, my mom had the foresight to keep the things that we really liked as kids...Lego, Star Wars, G1 Transformers, He-Man. Some I've sold, some I've passed onto my son. In fact, the whole reason I got back into Lego building was that two years ago, my mom told me to clear my old room in her house of all thetoys. My 4 year old son saw the box for set 375 (the yellow castle) and asked me to build it. And that opened up my sons love for Lego.