Your local bargain basement store should sell the multi packs of batteries, I know here in the UK you can go to PoundLand and get a pack of 30, combination of 15 different popular batteries, two of each. At £1, they’re a steal. I use them to replace the batteries at the local charity shops, which is something I do free of charge, just a few hours a week.
If you are unable to do it yourself, take it to a key cutters as they usually do watch batteries and will be a hell of a lot cheaper than a high street jewellers.
Are you in the UK?
If so, send it to me by signed for post, I’ll replace the battery for free and then return it.
Email me -
[email protected] for more details