Vintage grips has them, but there are three sizes for .38 cal IJ revolvers, and it depends whether you revolver is hammerless or an exposed hammer type - you need to measure your gun and compare those to the measurements for each of the three grips.
The screws are not included, but Vintage Grips has them if you order them also.
Measuring backside of right panel (vertical not diagonal) 2 17/32" long
1 1/8" wide across center of screw hole @ butt
Dimensions / Sizes for the Iver Johnson .38 Break Top Revolver Grips.
Measuring right panel (vertical not diagonal)
2 7/16” @ longest point
1 1/8” wide across center of screw hole
1 5/32” wide across center of pin hole
Iver Johnson .38 Brk Top Rev. w/Hammer
Measuring back side of right panel (vertical not diagonal)
2 ½” long
1 1/32” between “ears” – tip to tip
1 1/8” wide across center of pin hole