John,

Welcome to C&V. Great to have you. I'm not certain, but I don't believe that is the original stem for your Sports Tourer. The big give away is the rust. The stem pictured looks more like the one from a Varsity. I say I can't be certain because I've never been in the presence of a Sports Tourer. But I have two of its close cousins, a '71 & '72 Super Sport, and they have an aluminum stem made in England which has an "S" on both sides, just behind the bar clamping ring. I believe the Sports Tourer had the same stem. Now with all that said, I wouldn't worry about ditching the one in your picture.

If you look closely in this picture you can just make out the "S" between the brake lever extension and the bar wrap.