Hi and thank you for your question. Despite all the marks and stamps you may see on the handle, the only way you can know for certain if it's gold or gold filled is to have the metal tested. A gold test can be done on the metal by a jeweler or gemologist. The test should not be expensive. You could buy a gold testing kit and carry out a test at home but if you're not a dealer or collector this method may be impractical.
Does the store or retailer from which you are considering purchasing this item have a refund policy in place? Ask the dealer before you purchase if you could have a 5, 7, 10 days (however long you think it will take you to have the test done) to examine the item and if it doesn't meet your requirements, you can send back for a full refund.