OEM rear shocks for 2002 Tahoe LS 5.3 4wd with 104,000 miles?

[pounder86]

Bought this vehicle new with towing option. It's used for daily transportation, frequent towing a 17 ft aluminum boat and occasional 4wd use if needed. I replaced the front shocks a few years ago. One of the rear shocks has a leak. I'd like to stay with the original factory set up as it's worked well for my use.

 

Are Delco 580-354 GMs the OEM mechanical load leveling rear shocks, If not what is or what else would work as well without compromising ride or handling? Where to buy for lowest price ? Thanks.