Couple things. The 36M saved would be from the Pelicans persective. That's of course if they can pull off two seperate trades because no team is going to take on both those salaries ( Gordon one year and Tyreke three years). Both are guards which the Spurs aren't currently in short supply of. RC Buford, ever since the RJ trade hasn't been willing to gamble on big player contracts. Without the need for guards and the available cap space in the future, Tyreke is a no go and Gordon really isn't an upgrade over Mills at this point.
If the Spurs mak a move, it will be one of those far less talked about deals that has less to do with putting them over the top and more to do with regular season minutes eating and backend of the rotation depth at SF. I'll be shocked if the Spurs are part of a blockbuster. If they are, it would almost certainly be a three-way.
Also, Belinelli isn't going to be traded. As bad as his defense is, Gordon and Tyreke haven't proven to be any better. If anything, you'll probably take away from the offense because those players need the ball in their hands to be successful.