Most small dings or bends in an aluminum prop can be repaired for a reasonable price. If you do repair, make sure the shop does not file down the blade edges thereby reducing diameter. If your damage includes bites or chunks out of the blade, you should consider a new prop.
Keep in mind that while aluminum propellers can be welded back to look like new, there is significant strength loss when you do. Since a light tap could then put you back where you started from, you shouldn’t spend money on an expensive repair. Stainless props cost more to repair than aluminum because the material is more difficult to work with, however, once properly repaired, they can be as good as new.