Anyone point me in the direction of a Clinic / Hospital that does this? I would rather somewhere not overly expensive..

I believe this is only done at the government place across the street from Suriwong bookstore. Hospitals don't do it. You could go to RAM Hospital and they could give you the exact address of the place.

You might want to check the airport. I made it in Phuket airport about 5 years ago, quite cheap.

In Chiang Mai there is ONLY one place to get the Yellow Fever Jab

Its as the other poster stated, and the price is fixed

I cannot remember who much I paid

Forget going to hospitla's etc,

You probably know this, but anyway, if you are going to a Yellow Fever area, make sure you have your official original certificate of vaccination (not just some card). You will not be let back into the country without it