I too take all the it was made for Garcia claims (including the one that accompanied Old #10) with a large grain of salt. Nevertheless, I would expect a real Irwin guitar to be worth substantially more than an Oasis, Hyak, Dolan, or Becvar. I suspect there were very few Irwin guitars ever made. I have one that I'm about 90% sure is an Irwin, but it looks to be more of a highly modified instrument than one he built from scratch. I also really like the two ebay guitars, but at $85K the seller is dreaming in technicolor HD surroundsound.
Bill, tgo