Fleetwing wrote:

(I had not heard of 3-in-1 Oil as a way to rejuvenate a ribbon; may have to give that a try.)

Typically collectors will use WD40. I've never used 3 in 1 either, but I imagine the WD would be easier to apply. Here's how: http://munk.org/typecast/2013/10/23/using-wd-40-to-bring-an-old-typewriter-ribbon-back-to-life/