Why are lifters so much? Can I junkyard one?

[cp2295]

Why are these lifters so spendy? And is that little plastic funnel thing needed? I was cleaning the block off, cleaning the pistons all that good stuff, and I noticed that one lifter had the plastic funnel thing missing. I looked around, couldn't find it. I'm assuming while spraying the block with an air compressor it probably popped that thing off and I didn't notice it. Anyways how important is that thing, and if it's super important would getting a lifter at a junkyard be alright? I know they're roller lifters so It seems like the wear on the camshaft would be very minimal.

Could I just grab that little plastic thing off a lifter from the junkyard and pop it on mine if it's important the lifters remain in their proper spot?

Another question, I'm replacing the valve seals, what all should I replace? Can I reuse guides and locks and springs? Or should I replace those things? Also what about the valves themselves?

Thanks, Chris

 

[cp2295]

Oh and also how would you go about cleaning the lifters? B12 and then soak them in oil?