[71cadc10]

another GM lifter that is considerable upgrade over the LS7 (which I might be wary of the really cheap ones out there right now), is GM part no. 88958689

these work well for higher rpm use and can be found under $300 if you shop around.
preload is critical on these, you will need the ability to check zero lash with the cam installed in the long block, and then order pushrods to get you in the .020-040" preload range (cold). They are actually a real good value for the price.

I've seen what Comp lifters do to good engines when the lifter wheel ends up in the pan...so I can't recommend using them if they were given to you.