I suspect the earliest models would do exactly this - it would play upon the familiar feel of pistol and rifle to make the transition easier. But after they'd been accepted? There's no need for a stock on a laser rifle as there's no need to cinch it up into your shoulder to account for the recoil. Depending on how the technology works, there might not be a need for a long barrel - no need to control the direction of a physical round, and no need for rifling. Other needs would become paramount. Perhaps placement of collimating mirrors, or the size of the power pack providing the juice. Second or third generation laser weapons might look slightly different from modern slug throwers, but fourth and then on would likely look far less so.
Very interesting, and hard to predict, if laser rifles can be made shorter than modern rifles, then perhaps we will start to see some interesting shapes in weapons. The other thing to think about is the weight, the stock is not just there to transmit recoil to the shoulder, the point of contact with the body also makes a rifle easier to support and aim, holding a rifle by the pistol grip, extending it the arm, and then trying to hold it steady may be a useful exercise, but you are not going to be able to maintain any kind of aim. But then, perhaps second or third generation laser rifles could be worn as a kind of arm harness, if the length can be kept short.
Of course, as you point out, they won't need rifling, so we should probably just be calling them "laser guns".
Will we find out in our lifetimes?