So, this has probably been addressed before but I've been away for a while so, I just noticed that all of my PMs before 2008 are blank. Is this fixable, or are they lost forever?

7 years back? I'm sure we did an upgrade way back then and we had a database crash due to failed log rotation scripts sometime after the last move. No backups exist from that time frame anymore.

In short... sorry, but no.