The LED pcb appears to be riveted in place. Easy enough to drill out but re-securing it could be annoying.
That looks like an XP-E2 so any XP series or 3535 footprint should work. A larger die will produce a softer broader hotspot.
You'll probably have to reflow a new LED onto the existing PCB. Take a look on youtube for examples of how to do that with a hotplate.