Although rechargeable, L7 replacement cells are too low in capacity and there aren't any 3rd party vendors that do cells for the L7. Fortunately the beam pattern is very even and a bright centre spot. Please be aware that L7 is a twisty at the head and the TC is a fixed TC. I used to have one but not anymore...
If you can take the larger size, how about the Pelican 7060 instead of the Surefire L7, it would be brighter and throw further but most of the body is polycarbonate and it feels different then the L7.