The sticker on the side that is suppose to stay on permanently has fallen off, so I have no idea what model or size of this stapler. It was taken apart in an attempt to fix it. It appears that the spring broke on the slide and was unable to reattach. The slide does not slide and is also missing several bolts. I did a small amount of research and this could Model S-763, but I do not know for sure. In one of the pictures there is a ruler measuring 1/2" where the