Padlock with Missing Key

This is the padlock on the ammunition trunk in the basement which contains a number of interesting things of Dad's. We clearly got into it in 2018, but the key is now missing. Mum keeps suggesting we phone a locksmith and claim it is an emergency "because the deeds to the house are in the box", so far I have been ignoring this suggestion. My sister has suggested polling the neighbours to see if any have bolt cutters. I'm thinking this isn't a priority concern at the moment.