Hi, the job of search and replace URL in the database is very common while migrating a WordPress site. You can do that in many ways in general, not specific for Meta Box by using:
WordPress search and replace tool: this tool is one of the best tool to do this job with GUI
WP-CLI search-replace
command provides a same way to do that with command line. If you’re using Windows, you might want to follow this tutorial to install WP-CLI on Windows.
Both tools allow you search and replace a string in the whole database or in a specific table (wp_postmeta).