I may have something for you.
Spare bulb, that is. Our station got a large sample [img]/ubbthreads/images/graemlins/grin.gif[/img] of spare high-output bulbs. I got two or three extra. Free to anyone with BigD. Must provide proof of ownership Big D Lead-Acid.
Extracted from my PM, for the benefit of other CPF'ers:
"Hi, I have a Big D Lead Acid (based in no small part on your recommendation in this thread back in August) and really enjoy it. If you still have lamps, I'd love 'em. Let me know if I can PayPal you something to cover your postage.
One unusual thing: My original Big D lens got a "melt mark" in it. Has that happened to you in your extended usage? I called Pelican and they mailed me a replacement lens right away. The woman on the phone was very friendly and helpful, she said they hadn't heard of that happening before. I asked if they wanted me to send back the bad one, and she said no need.
Also, have you tried the low power "backup" lamp? I haven't, but am wondering how much more runtime it would have in exchange for reduced (hopefully not totally "worthless", despite your comment) brightness. I would consider using it if I could get, say, three hours out of the battery -- would come in handy when working on a project in the garage and using it to illuminate the underside of a vehicle.