A would love to pay for a Perforce on a reasonable subscription basis, too. Had no luck to find any such provider, too. I think it would be a good way for Perforce to promote their tool. $740 is just to steep to lure in people. Sad to see, as I still consider it the best cvs out there (in terms of having control and getting work done).
I also have (for a personal project) a locally installed Perforce.
As for file security:
Well, back up the entire Perforce Folder and whereever P4ROOT resides (normally in that folder) on a regular basis. Shut down the Perforce service before you do, fire up afterwards. On Windows, I found Cobian backup to be a great tool, to do all that in combination. I am not sure, if Perforce would be ok with "on the fly" backup, I am just not taking the risk.
Such regular full backups should be considered mandatory, even if your Server resided in Fort Knox. After all, there is hard disk failure but also the possibiity that your perforce structure gets corrupted. Although I can't tell of a single such incident with Perforce.