oil and questions

first well timing chain in my tucks 305 has too much slack so we decided to change it and the cam. this is what the top half looks and the valve covers were just as clean the oils we run. Are mystic 20w/50 and lucas by 20% volume in all our cars and truck. We were expecting worse becuase of the mileage. it is a never rebuilt 82. Any ways we(that is my wife and I. What happened is that I suffer from bad arthritis and just recently ,when I found this place , while at work unloding block from a delivery truck the decking gave way and I fell through so my injuries keep my from doing anything. So she does the work while I guid her through the steps and she likes doing it wish I had know that 17 years ago=) we found about 2/3 of the push rods are lose we will be checking them for bends of course. So here is my question
If we find they are bent should we go ahead and swap the rockers arms and valve springs to be safe or leave them?
Pleas dont say get a 350 we like the combo in this truck it has good low end powerd and we have pulled some crazy stuff with it hell we got a speeding ticket with it with a full pallet of floor tile in the back about 800lbs. Great gas milage for this size truck long bed Sierra about 17 on higway it a 350 pound load we checked.
so back to the questions should we do the rockers and valves or leave them alone? And if we do should we just do a comlpet valve job? what parts would you recomend ?