I just picked this bike up for cheap. It's all original in nice shape but I believe it to be a lower end model. 1024 frame , bolted Araya steel wheels, 10 speed. I wanted to put a set of racks on, bar end shifters and better wheels to make it a light tourer. Any thoughts or suggestions? The frame fits perfect. Wardie
Ride it like you stole it.
It is a lower end Miyata but one from a decent era when they were all pretty good- so don't fret about adding a few accoutrements to make it more pleasurable to ride. (Just don't do anything you can't un-do)
I commute on an older Miyata 10 speed, rack and fenders, I think it's a higher end model than yours but hi-ten. It's delightful. I think it's about 37 yrs old now, looks shiny new. Plush ride. As long as you aren't expecting your Sport to cruise at 17-20mph I think you'll be happy. I kept the original stem shifters as well as the drive train & steel wheels, learned to love it as a package.
If you are serious about touring in it, you might do some hill climbing and a century as a test...see if you can live with the weight, wheels and gearing.