2007 Silverado Rear end rebuild/replace options.

[Dustint]

I've got an 07 silverado and during inspection the dealer found metal shavings in the rear end. The previous owner must have ran it pretty hard as the two side gears within the third member are pretty severely damaged.

The dealer is quoting me roughly 2200 to replace broken components if they do not find any additional damage, and there is some concern due to the amount of metal floating around in the rear end as to if any floated down the axle tubes and such.
Replacement labor included with a new rear end basically all new minus brakes, is roughly 2600.

I'm not finding much for options on replacing just the third member or any alternatives aside from finding a used one via craigslist or something similar and of course that would be used components.

Are there any options out there that you guys have used for replacing the complete third member, any posi type units that may be available or another option I'm not considering? 2600 for a stock 8.6 rear end seems awfully high to me when I have around that in a custom 9' rear with eaton trutrac posi unit for my 48 3100, which is a far superior rear end.