I have an Iver Johnson 22 "Supershot" that bares some slight resemblance, but the IJ pistols that I've seen are considerably larger than my pistol. The picture that you provided is very close, but there's a few differences. First, the frame on mine is curved at the pistol guard whereas the IJ is more squared off. The frame in your picture also extends further from the tip of the trigger guard than mine does. Second, the cylinder in mine is smooth and shorter. Lastly, the hammer spring in the grip is much different than the ones that I've seen in IJ pistols. This one more closely resembles the springs (a single piece of metal) found in older Colts.
Like I say I'm away from my text on the subject but it's a H&R clone of the IJ IMHO or a variant made earlier. Also any clean sharp edges or rounded ones could be the result of a hammer monkey refinishing it .
I'll look tomorrow evening for ya when I get home.....Stay safe !
I think what you have is a Model 1900 Iver Johnson .22 Revolver built for a reseller like Sears and Roebuck or Montgomery Wards who may have specified the "Scout Model" designation. The lack of cylinder fluting is consistent with that model; the checkering on the grips is Iver Johnson's signature design for that period. Iver Johnson made minor changes in their guns almost yearly while the overall design remained basically the same.
The high serial number indicates a maker who has been around for a long time who made a lot of guns. Iver Johnson was founded in 1874 IIRC.
The three digit number is the "drawer number" used in the gun assembly shop to assure that all the matching parts for a specific gun are kept together during the manufacturing process.
Your gun is probably the 6" model... be sure to measure the barrel to the cylinder, not the frame.