1996 Ford Ranger Starter

My truck recently wouldn't start with a clicking sound when I turn the ignition. It will start when a screwdriver is placed on two bolts of what I believe is the starter. I was told this will only work about 50 times until I need to get it replaced. From apperance the part I'm placing the screwdriver onto (I assume the Solenoid((SP?))) Is what needs replaced. I looked on advanced auto parts and searched compatible parts and looked like the smaller piece of the starter cost about 20 bucks and the entire thing is 100 or so.

My main question is, the fact I can start my truck with a screwdriver, means the starter is fine correct? Just the solenoid which from what I understand regulates voltage needs replaced.

Thanks for any help. This is my first thought into repairing my own vehicle, I usually rush it to a shop but when moneys tight moneys tight.