I don't have numbers for some of the players so I'll estimate that the Rangers are at about $38.3 million in cap usage. 50.3-38.3 = 12 million to spend. probably want to subtract 2-3 for trade flexibility. leaves around 10 to spend.
These aren't meant to be lines, but rather to show holes.
fyi. Montoya adds 1.8 to the picture if he plays with the big club. I can see why Sather would want to trade him now. $10M does not seem like enough to sign both Gomez/Drury AND Nylander. No wonder those talks have dragged out. I wonder if you see the rangers make some moves to clear cap space.