Firstly, insurance would only be one option once markets had been freed. Charitable organisations could provide treatment for those unable to afford insurance. Indeed many of Britain's most famous hospitals were founded as charitable/religious institutions in the pre-NHS era, often with money donated by generous philanthropists. Moreover, in the late 19th century a large proportion of the population obtained health cover through mutual organisations such as friendly societies. Numerous options would emerge if voluntary solutions were no longer crowded out by coercive state provision.
Secondly, I don't accept the arguments about the limitations of health insurance. Insurers can lay off risk using reinsurance markets. And there is no good reason why elderly people can't be insured - for example through long-term plans that smooth out premiums over time. Equity release schemes could also be used to fund healthcare premiums for the many asset-rich but cash-poor pensioners.
Finally, it's important to point out that funding problems in general would be diminished by the deregulation advocated in the article. Entrepreneurship and innovation would increase productivity in the health sector, making treatment more affordable.
*facepalm*
