There are no after market parts available for these guns and so a gunsmith would have to adapt something. Mounting a laser sight might be easier.
A shotgun.
A shotgun made for Smith and Wesson, sold under the Smith and Wesson name.
$650-$1000 used
Standard Catalog of Smith and Wesson, 3rd, ed., by Supica and Nahas can answer your question.
It will be marked on the barrel
50-350 usd
Needs to be examined by a gunsmith.
100-400 USD
NO sn data for this S&W
50-450 usd
50-360 USD or so
350 or so