I just bought some battery parrallel battery adapters on Ebay for some of my bigger D lights. They take 1 or 2 AA batterys. They are probably not as nice as the ones that Aventrade sells, but are much cheaper. I had to change the springs on the lights so that the last adapter would make contact with it (it is recessed). Anyways with shipping $1.00 to $2.00 each. For the price I am very happy.
SALE-Battery Adapter AA to C or D-rechargeable NiMH NEW
SALE-Battery Adapter AA to C or D-rechargeable NiMH NEW