They are being made.
Model 15
It should be a model 15-2 and manufactured in 1979.
The Dan Wesson Model 15 was manufactured from 1970 until 1992. This revolver is known for its interchangeable barrel system and is part of Dan Wesson's line of double-action revolvers. Its production spanned over two decades, during which it gained a reputation for quality and accuracy.
100-400 USD or so
Dan Wesson is now operated by CZ USA. Barrel nuts are available for about $15 plus shipping. See the link at the bottom of this page to link to the CZ parts page for Dan Wesson Revolvers:
Is it a model 15?
The Dan Wesson Model 15-2 with the serial number B005158 was manufactured in 1976. Dan Wesson revolvers typically have their production dates determined by their serial numbers, and the B series generally corresponds to that time frame. For precise information, consulting a Dan Wesson historian or reference guide may provide additional details.
If it is a blued 357 with adjustable sights, it is probably a Model 15.
With the serial number that you have supplied,your Smith and Wesson model 15 was made in the year 1950.
The smith and wesson model 15,4th change (15-4) was made by smith and wesson in 1977.
Yes, S&W made a Model 15-3
67-77