They can afford both Stastny and another scorer if they want, they'll have 10-15m after the RFAs and Callahan/Girardi or trades. Hypothetically Stastny and Vrbata might cost 12 or so.
Again, you are failing to realize that the Rangers might trade for a young player that comes in, dominates and then wants 8 million a year. Or, lets say a Duclair comes up and by year three in the pro's he's a 35 g 50 A player despite Al and his negativity. How will you pay him when you sign some dope like Stastny to a 7 year, 42 million deal? Or perhaps Lindberg, Miller and Fast by age 25 are all 20 g, 45 point guys. You are talking 11-12 million right there.