I 'toured' from Cleveland OH to Madison WI on my '75 Fuji S-10S. It has a long wheelbase, has eyelets for both rack and fenders, and once I added a triple crank - Voila! Weight as pictured is still under 30 pounds.
Is it the 'best' touring rig? Probably not, but I've gotten a lot of miles on it in the past 37 years! 45,000+ and counting. I'm also planning to take it on a 1050-mile trip next August/September because it has never let me down!
I wouldn't hesitate to follow
most of the recommendations given thus far. While the Miyata 1000LT is the top of their line, the lesser 610 is also worth looking at. Same goes for the Miyata-built Univegas. Or the 80s Fuji Touring III, IV or V.
The list is a long one. The main thing is to 'Enjoy the Ride!!!'