I assume that you don't have a backup of your data hence the need for them to work in another unit.
All is not lost because you have them as standard drives. All you need is a USB/SATA caddy or adapter with its own power supply, a Linux computer, or a live Linux DVD and another disk with enough free space to hold all your data.
Boot Linux, computer or live DVD, plug in the disk mounted in the caddy or adapter and, if you are using an external USB drive for the backup, that as well. Now it is a matter of transferring your data from the NAS disk/s to the storage disk or disks.
Once you have a backup put the disks into a new unit, format them as standard disks and restore your data.