I just received this watch last night from fellow forum member ghostzapper, who is a great guy by the way, thank you for a smooth and well packed transaction!!.
So apparently this 6138-7000 slide rule spent a decent portion of its life safely tucked away in a draw and is in absolutely outstanding condition. The case lines are perfect and nice and crisp and there are zero marks on the outer edge of the rotating ring. If it has ever been polished, it has been done very very nicely. The pointer ring is after-market but apparently everything else is original. It keeps excellent time too! The hands are a sort of almost flourescent looking red/orange color. It has the original acrylic crystal which actually confused me at first until I found some catalog scans that show acrylic was the original material on this particular model (apparently the only 6138 that didn't use hardlex..). Its also on an original bracelet as well which is a huge bonus!!
This is the first of these I have owned and great clarity reference shots of known original examples seem hard to come by to judge the case finish etc...Sorry for the cell phone pictures but I wanted to share and I was at work. Will post daylight enhanced ones when I get a chance.