Despite the older products not being supported, the method of McAfee's "Drop in Engine and DAT" should work on products since VirusScan 95! McAfee just can't test (and fix) problems if there are any though.
You will need to update the engine first, then the DATs. I do not think the VSE 7.x series had an option for PUPs. SuperDAT or a manual update is what you'd need to do to get started.