Many of the Spanish copies of Smith & Wesson revolvers looked like the S&W on the exterior, but the interior workings often looked a LOT more like a Colt, with a V main spring.
You'll only know what you have once you get the grips off and start looking at the layout of the interior of the frame.
It's tough to tell, but I don't see anything that looks like a mainspring strain screw on the front face of the grip frame, which would mean that it's a Colt-style V main spring.
Finding parts for the old Spanish copies is virtually impossible, meaning that you'll have to make them.
"The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza
Baby Jesus cries when the fat redneck doesn't have military-grade firepower.