Thorfire TK05 dead. Driver available?

Light has 20 ~30 hrs. on it.  Maybe.  Always on L or M.  It started flickering a few months ago.  Then it became reluctant to power up at all unless tried multiple times.  Now it's just dead.  New cell does nothing.  Removed lens & reflector, put pressure on emitter to make sure it wasn't loose.  Never used anything in it except NiMH or alkies.  Everything's clean.  I can swap the head with another operational TK05 and the problem follows the head.  No response from a PM to seller Thorfire weeks ago.

I like the light & would like to salvage it.  Any aftermarket driver options?

Thanks all.

slmjim