Your best bet is always to locate old stock ones, what size and make are they?
If you are good at panel beating and if they are brass ones then take them to your local plating shop and have the chrome and nickel stripped first before attempting to straighten them.
I have found 70 degree LPM metal is ideal for doing the panel beating repairs. .... pour the metal into a straight section of rim or use an identical straight one (use plasticine if needed to stop it pouring out), then move it round the rim to a damaged section and gently tap out the wrinkles and dents. You can soon remelt the alloy and to remake the former if it starts to loose its shape. You may need to anneal the brass several times as it work hardens quite quickly. A few hours work should see it straight enough for polishing and plating. If brazing repairs are needed this can be done with a blowlamp but its quite tricky on thin sheet...
There are firms who specialise in headlamp repairs for vintage/veteran cars who could certainly do this work or even make replica rims for you...but you will need deep pockets...
Grommet
