Media blasting is using little particles of something that won't eat into the frame, rather than sand. Some people use plastic beads, some use bits of nut hulls, there are probably others.

My story - a few years back, I attempted to repaint a Raleigh Professional frame that had been repainted very poorly some years before. Stripping was a chore, and even though I thought I did a pretty good job on priming, the result was quite disappointing. I sent it out to be painted, and I'm very happy with the end result.

Yours will be a 1" threaded headset. Don't worry about the article you found. Your bike is from the 80's and Raleigh was no longer using steerers with that odd threading by then.

I think a Tange Levin or Passage would be a good choice for the headset (English thread). Velo Orange makes some called Grand Cru, which are pretty nice, and not especially pricey.