Otto Porter Jr for Aldridge and one of the following (in order of preference for the Spurs): 2nd round pick, 1st round pick or Lonnie Walker.
I don't know what it would take for the Bulls to consider the trade, but I think I would be willing to part with any of those assets.
Why would the Spurs consider this trade?
Otto Porter is pretty much the protypical player they are missing at that 4 spot. Porter Jr checks all these boxes:
-6'8"
-defensive minded player who is versatile.
-good 3pt shooter.
-positive impact player on both side of the ball.
-and the best trait yet: he's only 27 years old. He fits this young core window like a glove. For real, I don't think there's a better fit out there.
Porter's one big question mark is pretty much a non-issue for the Spurs: his price tag. He makes Aldridge money (another reason why the trade is pretty much tailor made) and he probably would want to keep making that kind of money. Thankfully for the Spurs, they can allow to overpay a bit for him in the next couple of years. The Spurs can offer Porter a contract that not manybother teams around the league can. That should give PATFO confidence about retaining him past this season.
Why would the Bulls consider this trade?
The Bulls have two options:
-If they want to compete to make the playoffs, they can just keep Aldridge. They have no real starting center and LA would be an immediate upgrade on that department.
-If they go tan mode, they can just buy out Aldridge, in which case their gain would be the pick or a promising young player in Lonnie.
Either way, win/win for them.