Maybe you can get one for high 600K now? Maybe to mid 600K in the future, but I don't see it falling below 600K...
I am in Marin and we have Eichler homes in San Rafael (Terra Linda, Lucas Valley). The Eichler homes are quite sought after and you always have a lot of people who love the special features, design, floor plan and the community that comes with Eichler.
The past few years' Eichler Home Tours (Open Hearts, Open Homes) benefiting Hospice by the Bay. This always bring renewed interest to Eichler homes in the area.
Although the market is getting tougher, Eichler homes do tend to hold their values. A good time to buy will be looking for Eichlers that need updating, which can be great deals. I was a docent in the last year's Eichler Home Tour. The owner did outstanding job in modernizing the home while retaining the uniqueness of Eichler homes.