Looking for yarn substitute

[CaribbeanQueen]

I am working with a vintage pattern that calls for "Sirdar Majestic Wool 3-ply" yarn. I don't think this is produced anymore. How do I go about finding out what the weight and fiber was of that yarn so that I can find a substitute?

[GrumpyGramma]

Knowing the gauge the pattern calls for would help as you can then look at the ball band or info provided online to see if it's similar. I'll leave suitable substitutes to people who know more about the various yarns.