Ruger Mark I Target Model.... Price?

So my dad has a Ruger .22 Mark I Target model. We want to find out how much it is worth. Some body told us that it is a collectors item. I don't know about that.

http://www.cornellpubs.com/Templates2/Ruger%20Mk%20I%201952.htm
The manual looks similar, and the top gun looks like our Ruger


Any idea on a price on it?

Go to the Ruger website, and in their website they have a serial number database to figure out the year, if its really old it may be worth holding onto, but typically a target Mark 1 model will fetch only $150 at your local gun shop, or sell it yourself for an extra $50. They are fun, cheap guns to shoot, and second hand value is low.
I had a MarkIII Ruger target model that I sold because I needed the money, it sold for only $225, and I spent $435 only four months previous.

150? I'll take it. A standard mark 1 easily fetches 150 in nice condition.