It's likely leggy from needing a lot more sun, and cutting back won't help as much as providing better light (you'll just end up with 'lollipops'). Consider first which branches to keep, then concentrate on the lesser stuff. I think it should bud back as well as most other ficus.

Hi Lucy,
Thank you for your help. At present it has to stay indoor, of course, but it is at a west window and gets lots of sun in the afternoon. I'll keep working on it. I may try to post a photo soon.
Krys

If you can rig a high wattage one of the new spiral fluorescents within 6 inches of your tree for 16 hrs a day (if on one side, turn the pot daily or weekly) it'll be much happier!

"Above all, will it bud back on old wood?"

Follow the good advice you have been given here.

In my limited experience with Ficus, yes they will back-bud, even on old wood. Where the buds appear is mostly sporadic and hard to predict.

Get your tree to survive at this point as others have suggested, then when it can go outdoors, prune back to get rid of the legginess.