In theory there isn't a thrust effect if we're talking about a certification-type stall (1kt/sec straight, for example) because the thrust is assumed to be zero and the demonstration will be usually conducted at idle power.
You may have a gear effect on stall speed due to a wing-mounted gear disrupting the flow on the wing - instead of a nice airfoil shape in that part of the wing, you've got a big hunk of undercarriage sticking out, and a big hole where the bay is. Similarly, the nose gear and doors may be disrupting forward fuselage flow and reducing lift from the body.