Without trying to sound too harsh, you have no understanding of the gun & no problem whatever.
Slight upper (slide/barrel) play relative to lower (it's called a frame or receiver, not a handle) is quite common in autopistols and has little affect on accuracy.
As long as your barrel is tight inside the slide, that's what maintains the bore alignment with your sights.
If barrel & slide move together, the pistol is fine.
At the moment of ignition, your barrel is aligned with the sights on the slide as one cohesive unit.
There may be some slight differences in the relationship of the slide to the frame from shot to shot, but those are completely irrelevant with iron sights because the SLIDE and SIGHT relationship remains exactly the same from shot to shot, regardless of some slight lateral "wiggle" between upper assembly and lower assembly.
You'll see some degree of "looseness" on most autos nowdays, and it was deliberately built into the tolerances of the early Colt 1911 pistols
to assist reliability.
Contrary to popular opinion, a very tight slide-to-frame fit is NOT an absolute guarantor of accuracy.
It helps, but it's not needed on most "working" pistols.
As for a laser, it'll be fine.
The laser is a sighting aid, and generally not considered a "target-grade" sighting device on a pistol of this type.
It can be, on other designs, but not here.
In other words- even with a slight difference in the relationship between slide and frame from shot to shot (and it WILL be slight), there won't be enough difference to adversely affect the degree of accuracy you should reasonably expect from a laser on this platform.
You can easily zero a laser on your pistol, and it'll give you repeatable accuracy and repeatable point of aim/point of impact, WITHIN acceptable parameters for the design and manufacture.
Unless you have a degree of slide looseness way beyond anything the factory would let out the door, you have no problem with your pistol whatever.
Go shoot the thing & quit over-thinking it.

Denis