You should not ask for a number of stock options - you should ask for a percentage of the company.
In other words the number of stock options you get means nothing unless you put it in the context of total stock options. Its like saying you want 1000 coins and not mentioning the currency.
Without knowing your situation - tell them you want market salary and .1-.5% of the company in options. During negotiations value your options at $0 - if they happen to somehow materialize it will be a nice surprise bonus.