De Uberti is a silver exporter company out of Italy. Nearly all the pieces date from the mid to late 1900s. They were primarily silver plate. I don't see a number mark on the bottom of your cups indicating silver content, so they should be plated. They made a lot of hollow ware---from goblet to full tea service sets. Some of their sets even came in presentation cases. Based on the dove stamp they're likely from around the 1970s. They're are mint julep cups.
It's too bad you don't have the original box they came in. They should have been in a lined box with a letter or small booklet that actually tells the legend of mint juleps. It makes for a cute novelty.
Based on my guides and actual recorded sales, your set should have a current secondary market value in the range of $45 to $60..
Keep in mind that prices will depend on the exact condition of your pieces and where you sell them.
Etsy and Amazon are turning about to be a great alternative to Ebay and do sell worldwide. http://www.bonanza.com/ and http://www.artfire.com/ are pretty good up and coming online sites. Rubylane, Tias, and Cyberattic are great selling sites too..You might check out the consignment cost with any local antique shops. Some laces charge about 25% to 30% of final sell price, but in dealing local you generally have less competition. It's always worth checking out..Ebay is more or less a last resort. It does reach a lot of people, but the values tend to be lower. You will always get a higher value by selling it yourself as opposed to an auction or selling it to a dealer because they're looking for profits too..If you go with Ebay, consider a reserve..
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