There are NO "drop-on" pads to fit your rifle AFAIK - every pad will need to be individually fitted.
Just be sure to buy one a bit larger than the bare end of the buttstock.
The best way would be to remove the old pad via unscrewing it's two screws (hidden - look for 2 slits in the rubber) and compare it the pads F/S at local gunshops.
If the new pad's screws don't align with the old holes, fill the holes with carved wood dowels & drill one or two new holes in the proper location.
If you grind down the oversize/new pad, be sure to follow/extent the existing stock bottom, top, & side lines straight to the rear end of the new pad - or the result will appear clumsy at best.
You should wrap the end of the stock sides, etc, with masking tape before fitting, to protect the existing stock finish.
If it's done carefully, a professional-looking job can result.
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