Wiped cam/lifter?

Well, i dived in to it today. When i checked the lofters, two of them seemed colapsed in that they provided no resistance when being pushed in . All the other lifters seem fine.
Thought i should swap ina new set of lifters.

I had 2 lifters go bad on me at e-town last month,i changed them readjusted and car has been running fine since..