It is depending the status of the P/S set, if it stil had some pinch it could hold up just fine.

Indeed use some sandpaper to get rid of the piiting als also in the combustion chamber.

If the engine holds his idle easy the engine will run fine, maybe not that powerfull als a new one but for sure good enough as training and spare. As mentioned before there is nothing to loose to try this, afterwards you can still decide to get a new one or a new P/S set.