Hello Tim,
I looked through my references and online. There are a lot of photographs of the man, but I haven't been able to find any of his aircraft. Littlefriends.co.uk doesn't list any name or artwork on the aircraft. That doesn't necessarily mean that it wasn't there, but it would explain why photographs appear to have never been published.
You might want to try some of the books on the 4th FG that are out there, but I don't own any of them so I can't say whether Garrison's a/c are pictured. If you really want to get ahold of something, read this article:
Vermont Garrison, 78, Fighter Pilot in 3 Wars - New York Times . It lists the names and locations of his family members. They might have something.