I didn't bother rebuilding the master. Mine has a 400EX or 450R front master on it now. They're cheap and plentiful.
I found if the plastic coating on the hose is broken or gone it tends to rub on the tire when the suspension compresses.
I "restored" my front brake line (copying someone else's idea) by:
- chipping all the old crap off the line
- splitting some plastic ice maker line from Home depot and sliding it over the hose
- wrapping the whole thing with clear shrink tube
You can kind of see it in these pictures.
Somebody was making a very nice reproduction hose with correct silicon ends, etc, if you want to go that route. It's gorgeous.