Most likely the right "cartridge" if it was a GL key.
I have found a REAL locksmith is the quickest, easiest way to get a working key made. Might not be a bad idea to bring him a GL blank if you fear he may not have one. (I had my own, but he mentioned he was 'out' of GL blanks at the time)
A locksmith won't need no stinkin' cartridge either!!!