In that size, for that bike, something like the Monarch Plus would be a better match. Tons of shocks in the 7.5 x 2 size out there though - near anything should fit. Obviously you'll give up a little travel vs. the 2.25 stroke shock, but at least they ought to fit the frame.

7.5 x 2.25 is sort of an oddball. Sure it's not a 7.875? Or do you think you'd have room to run one of those without rubbing at bottom out? It would alter your geometry a touch though. Slightly higher BB height, slightly steeper HTA.

Or take the money for a new shock and get yourself a new frame, swap al your parts?