I had this problem with Burnout Paradise before. I think my best bet is to get one months PS+ and backup to the cloud, that way at least it will be tied to my PSN account.
I have replaced the hard drive in my PS3 and all I did was back up all my save data onto an external hard drive and once i replaced the hard drive in my PS3 i just re-loaded the save data.
Just completed the HDD change and everything went smoothly. Oddly it even kept all my old user ID after inserting the new drive which meant I didn't even have to re-enter anything. Just transfered my gamesave and I was good to go. Thanks again dhandes and s10train.