A.Y.
Its tough to find private practice SF OBs that support VBACs but SF General is very supportive of VBACs. Sage Femme Midwifery (Mission area) can hold your hand through the process. If you talk to the owner, Judy Tinkelenberg, she is sure to come up with some ideas. I know SF General is a county hospital but the doctors that practice there are from UCSF. Ultimately hospitals don't support VBACs because it takes too much of the doctor's time, SF General has 12 midwives on staff that take care of you until its time to deliver and get the doctor. Your chances of having a VBAC improve significantly if you work with a Doula, so you should look into that too.
CPMC is not very VBAC friendly and I believe St. Luke's closed their L&D unit sometime ago.
Good luck.