Dont change all the resistors! thats insane!
If you must, change the electrolytic caps, wax and black beautys.
The 3 leg thing is an integrator. Its very important, its a series of resistors and capacitors. You can make one, I have some of the schematics here.
http://boxcarcabin.com/integrator.html
Again with the resistors especially, dont introduce all that new chinese junk in that set, you are opening yourself up to nothing but a headache.
Also those cap values are very common, i can go to the local store and get them. Maybe look for them as 4700pf and 6800pf but i wouldnt change them unless they are wax or blacks.