The photo is too grainy other than to say it is one of two Scott numbers, both of minimal monetary value, although certainly of learning value. However, I was hoping you would have another try at IDing it with reasoning why you believe it to be a particular #.
If you don't have a perforation gauge handy, try counting the perfs in the horizontal direction. The perf gauge value is the number of perforations in a distance of 2 cm. The design for these stamps generally is just slightly less than 20 mm horizontally, so the count should give you a good clue as to the horizontal perf gauge for your stamp. There's only one 3-cent stamp of this design with compound perfs, so there's a good chance you may not need to worry about the vertical perfs.