Campbell Irvine is the de facto travel insurance firm for the Mongol Rally. When I contacted them I was quoted £117 for 45 days or £142 for 62 days. Kai then got wind of an annual (maximum 70 day) policy for £99. Having enquired there apparently is nothing extra included in the more expensive, shorter periods of insurance, so I requested, and received, a refund. It's a bit of a con if you ask me.