The aluminum 5.3's aren't as common as the iron versions (they came in SSR's, some Envoy/Trailblazers/Rainiers/even Isuzu Ascender lol, a different version but still aluminum came in some 4x4 Silverados from 05-07, known as the L33 or 5.3HO instead of the LM4, it made 310hp instead of 295) but I was talking $1000 for an engine with almost no miles, I see them going for 5-600 all day long complete with accessories, wiring, computer etc. The newer 5.3's (all 07' later and even some 05' and up versions) are a different animal, same basic design but the computer systems are different as they use the active fuel management and the lifter assemblies and what not are different. The iron ones I see for $200 around here with 80K miles lol, there is one in Alabama right now I've been eyeing.