The fork is from January 1982 so a 1981 manufacturing date for the frame is not unrerasonable. It's almost cerainly a 1982 model. Removed braze-ons further satisfy the era deduction. A 26.8mm post is indicative of a Tange tubeset. Unfortunately, almost all of their CrMo sets from this era use that post size, so it's almost impossible to further determine the exact tubeset.

You say a touring bicycle. Is there evidence of removed cantilever studs? Maybe the longer wheelbase is an illusion? You may have put 700c wheels with small tires on a bicycle intended for 27" wheels. That can easily add a 1/2" of apparent wheelbase.