If you're looking for industrial quality taps I would recommend MSC industrial supply, or Fastenal, or Travers tools. Another one is the Big Yellow book which I can't remember the name (old age) located out of Los Angeles. The 1st three carry many different classes of taps and sizes down to 00-90 or metric. from import to made in USA. Just my opinion but Irwin or Hansen are a commercial grade and won't be the same as the others. I'd be mighty careful tapping any tough material with them. Just google any of those names. They'll be happy to send you a catalog unless it's changed in the last couple of years.
dickr
dickr