I have seen one Rigarmi Hijo Militar for sale on GunBroker, well over a year ago. I didn't bid on it and don't remember what it sold for. That is as close as I have ever come to seeing one in the flesh. Incidentally, "Rig" is a contraction of Rino Galesi, IIRC.
On the subject of "Hijo", in the 1950's or 60's Iver Johnson made a top-break revolver for another company to sell under that company's name. Their model name for it was the "Hijo Quick Break" or something similar. (Bill Goforth, who literally wrote the book on Iver Johnson, talks about it a little here: https://
www.thefirearmsforum.com/threads/32-s-w.38262/ ) Maybe there is some other meaning to Hijo when it comes to pistols, or maybe it means something like "Junior"?