SMD aluminum electrolytic capacitors and TH caps are not that different in size. So replacing it per se is not that hard, even if the pads are damaged. A fiberglass "rubbing brush" can create new areas easily through the soldermask to solder the device to. What you don't know is whether there is any inner damage (if more than 2-layer board) and whether that is the only damage.
As for "knock on damage" , I suspect you would need a better picture to see possibly buried traces as with a board of more than 2 layers. Of course, the soldermask is black, so that is not easy to see, and an eBay seller is not going to send you an X-ray.
If it is just a 2-layer board and the price is right, I would not be that reluctant.
John