REPLACEMENT Rear Air Shocks 2007 Avalanche

I have a 2007 Chevy Avalanche LTZ  4x4 with rear Air shocks ,self leveling
I need to replace them , The air bags are leaking

I have Z55 and G69 RPO codes.

what is a good direct replacement shock ?

My current rear shocks are Delphi part # 15869657

http://www.amazon.com/ACDelco-580-451-Original-Equipment-Absorber/dp/B00EDQ19EI/ref=sr_1_1?s=automotive&ie=UTF8&qid=1437675064&sr=1-1&keywords=ACDelco+580-451


Everything you need to know:
http://chevyavalanchefanclub.com/cafcna/index.php/topic,131766.0.html

Thanks for the info