Wallace Sterling Sliver Grand Colonial

I personally would not spend any money getting them cleaned as it won't really increase the value. With current silver prices you are looking at $300-$500 for this set in silver weight and finding a buyer outside that range is nearly impossible as this set design is not desirable and there is very few people collecting flatware to begin with and practically zero people using to look it for everyday use. 

Current scrap value for Sterling (today) is $13.05 per troy ounce ($11.90 for a regular ounce) Just weight up the total for the set and it will give you a scrap melt value. You can try selling it on Ebay, some will pay a premium for replacement pieces above the scrap value.