I applaud you for wanting to keep it original. The Sprints are timepieces of history IMHO. When you go to a cruise night or car show, it will be the only one there, it is almost a certainty.

I will warn you that the Sprint paired up with the ST-300 is not a good combination. If mine wasn't original, I would ditch the auto in a second (I may eventually do it anyways). It's like having a dirt bike with 2 gears.