Mariano Autographed the Yankee Stadium Bullpen Phone

The final call.

The Yankee Stadium bullpen phone was apparently replaced during the offseason, since last year's showed up at Steiner Sports, signed by Mariano Rivera himself. It reads:

"My final call to the mound on 9/26/13. 652 saves."

RT @steinersports: So this just showed up in the office. @MLB_Authentic #ExitSandman

- MLB Authenticator (@MLB_Authentic) April 24, 2014

I can't imagine how much this would go for at auction. Maybe as much as this?