If there is anything then it will not be easy. Pretty much only pokemon and maybe final fantasy have save editors of any great note here.
You can try to dump the save and see if you can open it in a hex editor or something to see what remains of the save, and then either try to port that across to a new save, force the hash to be correct, or try to force load it with a version of the ROM with save checking disabled. Definitely grab a copy of your save at the first chance you have you -- if you start playing and overwrite it then chances are nothing is coming back.
What will probably be easier at this point is to load up the game with a bunch of
cheats and power level your way back to where you were.