Spurs total salary against the luxury tax -- $67,474,887
The luxury tax threshold is $67.865M, Spurs are $390,113 under it.
If Spurs sign a player today for the reminder of the season, it will $253,848 cost against the tax.
The soonest Spurs are allowed to sign Barry (if he is waived and don't sign with another team) is March 22nd. If they sign him that day for the reminder of the season with a min salary, it will cost them $117,858.
So Spurs can sign now a player and keep the possibility to sign Barry when it will be allowed by the CBA without going over the tax.
We will see what Spurs will decided to do, signing D-League players to 10 days contract, signing a vet who doesn't play or who will be waived by his team before March 1st or doing nothing. Spurs have the financial flexibility to do what they want.