Here is my update on how I resolved this problem:

1. Using dd to make an image partition to an external USB drive.
2. Run fsck.reiserfs --rebuild-sb on the USB partition. In this process, I had to select y to create journal to recover this partition. Once recovered, I made sure to manually check the integrities of the files.
3. Use mkereiserfs to format the unmounted damaged partition. Once formatted, re-mounted the partition and copied all the recovered files from the USB partition to this newly formatted partition to restore the data.
4. Checked the integrities of copied files before deleting the files on the USB partition.

Now, my system is back to normal with no data lost.