Another Set Back (very Frustrated)

I Have Been Working On My Car Since Last January. Everything Has Been Fine Until I Fired Up The Motor Last Week (360). At Idle It Runs Great, Once Over 2 Thousand Rpm It Starts To Have A Loud Knock. The Motor Is Stock Except For Cam, It Only Has 60 Thousand Miles On It, The Bottom End Seems Fine (but Who Knows). Im Going To Drop The Pan And Check The Bearings Today. Im Out Of Time And Money. Its Hard To Raise Four Kids And A Dart. On Minimal Income. If Anyone Has Any Suggestions, Or Knows Where To Get A Rebuild Kit Or Pistons For Cheap. It Would Really Be Appreciated I Need Advice And Probably Parts For Cheap. Thanks In Advance.