Substitute (not replacement) rear socket

The drawers slides were factory installed by Merillat the cabinet manufacturer. I need to move the drawer up higher in the cabinet. I can not get the slide to release from the socket nor can I unscrew the socket from the back wall of the cabinet. I removed one slide by bending it and finally pulling it out by brute force. I sawed off the end thinking I could use a Blum rear mount socket to remount it but it does not fit. The slide (has AGSB embrossed on it) measures just under 1/2" wide and is 7/8" tall (too big for the Blum socket.) I am hoping you sell a rear mount socket (one where the slide slides INTO it ..since my slide is a bit shorter now) that is tall and wide enough to accommodate it. Thanks!