The photos you synced to your iPod through iTunes are no longer in their full resolution, but instead are scaled down thumbnails of those photos. So if you do manage to get them off your iPod, they will be quite small in size compared to the original ones you lost.
In order to get them off of your iPod, you'll need the help of some sort of 3rd party software. Here is one option.
If they did happen to be full resolution photos, see this Apple support document.