Yes....if you break for spares it can be a better way to make the return on your initial purchase but is sad that the rifle would be lost down this route.
If your lucky enough to find a market for the sight, you may well get 20 to 30 quid for it. Dont forget some shops will often have original unused spares with which your well used spare is up against.
Stocks are tricky, with many enthusiasts and dealers accepting dirty stocks with the odd blemish here and there but bad stocks can be virtually worthless.