1931 Sc703 Or Sc703c?

Could you help me classify these two stamps, I have doubts if they are SC703 or SC703C.

Struggling to understand your doubts. They look to be two scott 703's. They cannot be 703c as they are not an horizontal pair imperf vertically.

I think you need to look at how you are cataloging your collection, otherwise you will soon frustrate yourself. I was always taught to look at the most obvious and simplest first and only then look at unlikely but possible alternatives.

My doubt comes from the non-perforated side. The truth is that I am learning a lot by seeing the possibilities of each of the labels and I am very grateful for your help.

Scott 703 was printed in 2 press-sheet formats. One of them was a sheet of 100 which was cut in to 2 panes of 50 for retail sale. There was an inked cut-line running down the center of the press sheet. This inked center line was not perforated.

The illustration below places two panes together to resemble a full press sheet and an arrow to show the column where your stamps come from - having a natural straight edge at left the inked cut line. Your stamps are normal 703's

For comparison and future reference, this is what an actual 703c looks like (not mine). This is a horizontal pair, imperforate vertically.