The recent team brought us a champion had the following players:
KG, a former MVP (2004), all nba 2nd team 2005, 3rd team 2007
Pierce, all nba 3rd team in 2002 and 2003
RA, all nba 2nd team in 2005, and 3rd team in 2001
All of them are all stars in the 4 years before 2008 (except PP, who's injured in 2007).
Looking at the all nba teams in the last 5 years, only these active players have made it:
LBJ, Wade, (Bosh made it in 2007)
Duncan, Parker, Ginobili
Durant, Westbrook
CP3, Griffin
DH, Harden
David Lee, Bogut
Randolph, Marc Gasol
Kobe, Nash, Pau Gasol
Melo, Chandler, Stoudemire
DW, Joe Johnson, Paul Pierce (KG injured in 2008)
Dirk
Bynum
Kevin Love
LaMarcus Aldridge
Al Horford
Paul George
I grouped them in their current team. As you can see, the teams with more than 2 all nba team players were pretty much the real contenders in the last 5-6 years(please ignore Nicks).
I admit it's a bit sloppy, Dallas Mavericks win the title in 2010 with only one superstar Dirk, but Dirk is a former MVP and they did have the defensive player of the year in their roster.
Apart from Mavericks, the other champions and and final teams: Celtics, Lakers, Heat, Thunder, Spurs, Magic(ok, Magic is an exceptions too, but i think you'd agree they are the weakest final team in the last 5-6 years) all have >=2 all nba players.
My point is, to get back to the top, we need to assemble a team with similar caliber. In the current roster, only Rondo qualifies this standard (all nba 3rd team 2012), assuming we keep Rondo, we still need another two to join him.
From the above list, plus two near misses(they scored more than or close to the guys on the 3rd team), we have the following players, who are still at the similar level as they elected, and (I think) are potentially available for trade:
Marc Gasol
David Lee
Brook Lopez
Stephen Curry
Kevin Love
LaMarcus Aldridge
Al Horford
Melo
DW
these plus some young stars have real potential for all nba team soon:
Anthony Davis
Kyrie Irving
Damian Lillard
Roy Hibbert
DeMarcus Cousins
John Wall
So to trade for established stars these are your targets. I don't think Stephen Curry, Anthony Davis, Kyrie Irving, Damian Lillard, Roy Hibbert, John Wall are tradable, so the real list is here:
Marc Gasol
David Lee
Brook Lopez
Kevin Love
LaMarcus Aldridge
Al Horford
Melo
DW
They are all bigs except DW, but then if we keep Rondo there's no need for DW. So my preference is here:
Kevin Love
LaMarcus Aldridge
Marc Gasol
Melo
DeMarcus Cousins
Al Horford
David Lee
Brook Lopez
If we can get any two of them, we will be back in the game right away. Otherwise, Danny needs to work his magic in the draft, or wait for some other young stud somehow becomes available.