Which ones are you talking about specifically? LMC sells a ton of lights for these trucks.
Without specific part numbers I can tell you this from experience, though. Most of the decent lights they sell are just Anzo stuff marked up a ton. For instance, part number 37-7350 on this page.
http://www.lmctruck.com/icatalog/cd/full.aspx?Page=67
Listed at $129.95, plus the flat rate $15 that LMC charges for shipping, brings that to $144.95. They're Anzo 111004s. I can verify this personally, bought a set of them from LMC for my Suburban, and then bought a set of these for the red truck.
https://www.amazon.com/gp/product/B0015PPZMC
Same exact product down to the packaging, for $50 cheaper than the LMC listing.