2000 ranger power steering leak

Hi All
I have a 2000 Ranger 4X4. There is a leak in my power steering system and I am looking for some advice. The truck started making some really bad ‘groaning’ noises whenever I would turn. Power steering also became very stiff. All this took place while we were experiencing some very cold weather (-35 Celsius, or about -32 Fahrenheit). When I got home I looked in the pump reservoir and the fluid was all aerated. I was low on power steering fluid so I filled it up and bled the system to get the air out (lots of fun in -35 with no garage). This solved the problem at the time. However, I was not convinced that the fluid level was just low for no reason, but I could not find a leak. Not wanting to damage the pump I chose not to drive it. It got a bit warmer out today so I started up the truck and the noise was back and the fluid level had dropped again. This time I managed to find a leak.
The leak appears to be coming from the end of the steering rack on the passenger side. I am not too familiar with this system, but there is a boot that is attached to the end of the rack. Right where the boot attached there looks like there is a seal of some sort. This is where the leak is coming from. Does this sound accurate? Is there a seal or O- ring in there somewhere? If so, has anyone replaced this on there own, or is this a job for the shop. Thanks in advance for the help.

Hip