Peavy has good value in terms of being a league average starter (roughly). So anyone who needs SP depth to keep on keeping on might want him, as the Sox did in 2013.
In terms of what he brings back, I'm not sure the Sox really need anything at the ML level that Peavy's likely to bring on his own. Our bullpen is fine. We're not getting a league average SP *back*. Assuming we're in it to win it, I can't see anyone really displacing any of our starters. Either the current cast (plus Pawtucket replacements) works or it doesn't. Victorino's healthy (for now), Nava's hitting again, JBJ is also becoming more productive, and we have a quasi surplus in X, Holt, Drew, and WMB.
So that leaves prospects, or Peavy in a package. In terms of ML ready players, maybe there's a possibility for something like Peavy/Gomes for a Gomes+ type player, or Peavy/WMB for a WMB+ player.
In terms of what he brings back, I'm not sure the Sox really need anything at the ML level that Peavy's likely to bring on his own. Our bullpen is fine. We're not getting a league average SP *back*. Assuming we're in it to win it, I can't see anyone really displacing any of our starters. Either the current cast (plus Pawtucket replacements) works or it doesn't. Victorino's healthy (for now), Nava's hitting again, JBJ is also becoming more productive, and we have a quasi surplus in X, Holt, Drew, and WMB.
So that leaves prospects, or Peavy in a package. In terms of ML ready players, maybe there's a possibility for something like Peavy/Gomes for a Gomes+ type player, or Peavy/WMB for a WMB+ player.