Rockwell pricing?

How much would a used but apparently complete (spindle to spindle) rockwell rear axle go for? I may have found one sitting around behind the shop I work at, and was wondering what it would sell for. This is either a 2 1/2 ton rockwell, or possibly an axle out of a big box van or flat bed truck, it's a massive unit. I might be able to get a picture of it tomorrow.