This might sound expensive, but data recovery software isn’t the kind of thing you use regularly, so it should be enough time to get your Mac back on its feet, or at least rescue the data. The unlimited app costs $89.95/£95.99 for one month (you can cancel at any time). That might not sound like a lot, but it’s more than what’s offered by most trials, and potentially enough to find what you are looking for or at least know it can see your lost data before you pay for a full licence.
If you are looking to recover a deleted file, EaseUS Data Recovery for Mac is a good option since it has a free version that is limited to 2GB.