how to enhance a crusty, old soundtrack?

[c-post]

A client of mine is reviving a couple of his old films with a distributor. He has the 35 print for transfer, however he doesn't have
the sound, except on VHS. What a joke! It is my job to recover/remaster this hissy, lightly fluttery, funky audio for layback to a new tape. This guy doesn't have a lot of money. (what a shock!)
Step number one for me is just to roll of the high end above 8000-10000hz. That cleans up the hiss. There doesn't seem to be all that much up there anyway -- the sound is probably from an optical track in the first place. The quality of the optical track is the real culprit. A denoise rendering pass over 90 minutes of soundtrack is not practical and probably would not gain that much benefit.
Can anyone recommend a device or plug in to restore brightness and clarity? I already have an Aphex type C Aural Exciter, but I've been thinking of calling a local rental house to get one of the higher end enhancement boxes. Any other recommendations for bringing soundtracks back to life -- quickly?

-John