I'm not sure what all the options are for headlights. Have you checked Z1enterprises, SiriusConInc and DavidSilverSpares? I have a bunch of spare healights hanging around. If you post a photo of what you have, then I can see if I have a match.
FYI, I drive around with my 350f headlight on high beam all the time now. The switch broke a while back, and I didn't feel like fixing it, so I left it on high. It definitely is not too bright for oncoming traffic, and the charging system does fine with headlight on high and my Dyna electronic ignition.
Camelman