4.) Reggie Bullock
Of the players that the Spurs acquired this summer, small forward Reggie Bullock is arguably the most likely to play a role on the team next season. Even then, he could just as easily be dealt, either before the start of next season or near the trade deadline. After all, he holds more value as a three-and-d wing than any of the aforementioned trade candidates on the Spurs.
In fact, San Antonio could seek a haul of four second-round picks in exchange for Bullock, similar to what they got for Josh Richardson by taking back Graham's contract. However, the team may not be in a rush to move him if they are able to reach the 15-man roster limit by cutting or trading other players.
One reason is that Bullock can play well enough to help the Spurs and could increase his trade value as a result. If that is the case and San Antonio is willing to take back his long-term salary, they may even get a first-round pick for him come the trade deadline.
Overall, Osman, McDermott, Graham, and Bullock are the four Spurs likely to be traded. And with training camp scheduled to start on September 27th, there are still a lot of moves to be made between now and then.