I have a Moto of the same approximate age, similar frame design including the "inexternal" marketing. I believe the main triangle is a lower-end cromo and the fork, chain/seat stays are all hi-ten. Still, the bike rides very nicely. It has some persistent issues in the headset/front end area that have defied all diagnosis, but I still use it as my daily commuter.
Routing the rear brake cable through the top tube was a royal pain! I think I ended up using an electricians fish tape to get the job done.