I wish I lived near you--I'd bring you a coat he could have! I bet I've got something that would work, leftover from my kids or my dad.
Are there any decent thrift stores around there? Maybe since nobody else has come through, you could at least find something temporary without spending too much? OR--make some calls to see if you can at least BORROW a coat, TODAY, from someone. Raising kids as a single mom, I learned quickly that EVERYone *says* they want to help, "just let us know if you need anything at all," but few are actually willing to put forth effort when the needs arise. I was blessed to have an awesome church family--all I had to do was say, "I desperately need a coat" and my pastor or youth pastor would MAKE it happen.
I just had a very similar experience on Wednesday, however (in terms of those who mean well and don't deliver, I mean--not the actual situation). This was a friend who has been really struggling, but refuses to let anyone help. She and her husband both have health issues, she was laid off last year and is making a "little" money doing Medicare insurance (which mostly only comes in October-December), he's a janitor--and now they have a daughter and son-in-law and newborn baby living with them, because the son-in-law is out of work. She finally got so desperate she asked me for help--diapers, formula, a prescription she couldn't afford to pick up... I sent out a "time to put your good intentions into actions" sort of email--and so far, ONE person has given $10 towards the stuff I went out and bought for this family.
It's kinda discouraging--but I believe that in the end, the greatest blessings are for those who put feet to the "good thoughts." (worded very carefully so as to not violate any of the forum "don't talk about religion" rules.

).
You are doing an awesome thing, and I hope someone comes through to help!!
EDIT: After reading pixmedic's post, I realize I neglected to say that I, too, would be happy to send along a coat, or maybe some clothes or shoes if I have anything that would fit him--I assumed that the coat needed to be dealt with TODAY, though, so I didn't mention that.
Tell us what size clothes, shoes, etc. Maybe we could have a TPF clothing drive!!