Bad Lifter 305 what to replace?

[kcackler]

I am very green when it comes to engine work, but I have narrowed my engine trouble down to a worn lifter and have read I need to replace the cam as well.

What other parts do I absolutely have to replace when I replace the cam?
What parts should I replace/inspect while I am doing this?

How do I determine what parts will work with my engine?

Truck is a 77 C10 with 305 and is mainly used for light hauling and just getting from A to B.

There are a couple pictures of the bad lifter.