Vitex grows well enough here in the SF Bay Area, but has never been all that popular of a shrub on the bay side of the hills. It tends to be a lot more popular where one gets hot summers and cold winters. In fact, I would say it is probably more popularly seen in places like Palm Springs or Arizona than here. There are a few wholesale nurseries that do grow Vitex, but not the cultivars you mention. Mail order will probably be the best source.

Just as an aside, not all natives are deer proof, and alot of the Ceanothus in particular are deer food. You might also consider some of the South African succulents; both drought tolerant and often deer proof. Cotyledon orbiculata in particular, and also many of the Aloes, although they will sometimes eat the flowers off Aloes.

You might get good information on most deer resistant and drought tolerant natives to select from at the natives nursery at Tilden Park. This is close enough to you that the deer resistance of particular plants would be meaningful...

Not sure if it's a urban myth or not but grey colored leaves are said to be deer resistant. No personal deer experience -just far too much with raccoons and pond fish..another long story..

Vitex agnus castus does very good here in Calistoga and I have seen beautiful specimens in Santa Rosa. We live on six acres with a good deer population and they have never eaten it. Also with large "Carmel creeper" ceanothus grown as a bank cover in 15 years only one year did the deer eat it down about a foot and it recovered better than ever. Al