You don't know the drive format, do you? Worst case, you plug it in to your computer, and accidentally wipe it. Most of those recovery programs aren't going to help if it is an obscure format. If you don't really know what you are doing, and it is important, send it away. I've used Restoringdata and they have been great. It will most likely be under $1000, but they can give you an estimate, it may be much cheaper if it is just rebuilding the FAT.
They have a few BC locations, I just send mine in.
https://www.restoringdata.ca/