It's hard to tell much from the poor resolution, non-driveside photo. However,the brake levers appear to be Shimano SLR. Based on this, in conjunction with the dark heaset cups, it may be 1987-1989 Shimano New 105 equipped, which was typically spec'd on mid-range models.

I can't see any visible tubing decal. Depending on the price point they wanted to hit, and assuming it is OEM New 105, there could be a fair range of tubesets. This was also around the time that they introduced their self-branded Ultech tubesets. Pending further info and better pictures, the best indicator to tubing grade may end being the seat post diameter.