Very cool guitar. Unfortunately, though, it appears to have been through the ringer. I doubt the tailpiece is original - too wide and I don't believe they were making fine-tuning tailpieces back in '74. The pickups have certainly been replaced. They were originally Hi-A's, and it might be even more - all of the Oasis guitars I have seen (admittedly not too many, they are a rare breed), have oval wooden pickup surrounds. These might have been replaced and the pick-guard may have been added. Also, the nut looks a little funky. I'll be watching this one and may make an offer towards the end. I'll be surprised if it sells at the asking price - Oasis guitars in original condition sell in the $1500-$2000 range in my experience.
Bill, tgo
P.S. I was just searching and found this post from a member of this forum from 8 years ago:
I owned Oasis #3 for several years. Gary Cooper built #1 for himself, then #2, Kool Bell's bass, then my guitar (maybe 1974?). It was stereo, with Hi-A pickups, 2 tones, a volume, and a master volume. Gary's wife's family was from Roseville. He left Alembic and they moved up there, where Gary started Oasis in Sacramento. I think it lasted about 5 years. After that he was a guitar tech at Skip's Music in Sac for about 30 years. He was a good guy to visit, always had lots of good Dead stories.