I agree that the prices do seem high, but consider the cost of a conversion which includes not only the cost of new headlight assemblies, but labor to modify the fenders and install them and the cost of repainting the fenders. If I really wanted a nice custom look, I might consider hidden lights similar to the coffin-nosed Cord. (BTW, I read that the word "coffin" was for some 300 years used to describe dessert pies before it was applied to burial caskets.)
The reason for posting here is that all of us are smarter than any one of us and there probably are other less expensive solutions. In a discussion with an AACA friend, he suggested that I use the more common 2337 bulb and socket. This would only require some minor modification of the headlight bucket.
I don't know what the real differences are between the 2331 and 2337 bulbs is other than Chrysler used the 2331's - any experts know the answer?
I ordered the bulbs, socket and Headlight Brightener from Ron Frances Wiring for a very reasonable $77 including shipping. If this works, it is probably the most cost-effective and quickest solution, The Ron Frances bulbs are conventional incandescents with 125/75 candlepower, but I can always try the halogen bulbs if I'm not satisfied with the brightness. And I can always augment the headlights with driving lights. Kanter
sells some nice vintage-looking driving and spotlights.
I'll polish the '39s reflector buckets and apply the re-silvering compound mentioned above - I have a business so I can get the good stuff. They are brass and in relatively good shape, so this seems workable. I'll post back to the thread with the results (it may be several weeks).