You should introduce yourself and also post this ? on the "POW WOW" to get a better response.
You should also post a WTB (wanted to buy) in the classifieds under Trad Bows. Mention your sons height so it will give someone an idea of his draw length. I bet you will get some positive feed-back. There are a lot of good condition bows out there that have been outgrown and waiting for a new home. Mention you may need a few "matching" arrows too, to get you started...
I wish I had a suitable bow for your needs.