Hello Forum;
There are a lot of experts in engraved S & W on this forum, so my input is very novice to say the least, but when I saw this Model 60 no dash I did some very basic research and quickly found that if the engraving is signed on the gun, and traced to a known engraver it does indeed enhance the perceived value. I say perceived because, as with any "art form" beauty and value are really what you see as the "buyer" (one mans beauty may equal another mans ugly). The asking price on this Ben Shostle (Founder of Firearms Engravers Guild of America) was right at $2,000. I thought about doing my usual dickering and almost lost it to another guy, by waiting one day to do some basic research. No one would think about paying $2k for a Model 60 from 1981, so its all in the fine detail, the craftsmanship, the execution, the materials (check out that sterling silver Rams head and the detail in the rams eyebrows!), the big horn sheep stag grips, etc.
This one Letters as shipping to a supplier in Indianapolis, Indiana, less than 45 miles from Ben Shostle's Gun Room Studio, where he performed his art work of "scratching up" S & W's.
For the OP: take a strong mag lite and a magnifying glass with you for hand-on examination before making any offer....no provenance would offer a lot less to see what goes. If the grips look real (stag, etc.) ask the owner to remove them for a look under the grips. I would not attempt to take off grips if I don't own it as they could be brittle, or have a hidden crack, and you sure don't want that while you are handling it.