Richie, no way they'd disrespect Ginobili by offering him $5M (relatively speaking, of course).
By making numerous reasonable projections (Ginobili re-signs for $7-8M, Splitter for $6-7M, Neal and Jackson for $3M, the 1st signs for $1M, Bonner, who's non guaranteed, is waived, Mills, who's got a player option, opts out, while Diaw, who also has one, doesn't), I've got them at about $52M committed for next season. The cap is projected to be around $60M and the tax $70M.
The best free agent options are: Smith, Blatche, Brand, maybe Landry (player option), West, Hickson and Millsap. Even if Ginobili took $5M, they wouldn't have nearly enough to sign Smith or Millsap, while Blatche and Hickson aren't "Spurs". That leaves Brand, maybe Landry and West.