These are the first aftermarket wheels I've ever seen with the 4 X 160 mm bolt pattern.
I tried to enlarge the photo to see the printing in the center cap, but could not get it large and clear enough. They do look really good and hopefully somebody will have the info you need.
I don't know which would be more cost effective if I wanted to change the rims on my Trabant. LDM tuning sells wheel adapters for the 4 x 100 mm VW and Fiat 4X98 mm bolt pattern.
I've got several 4 X 98 mm Fiat rims. Looks like it would be cheaper to have a machine shop remove the 4 X 160 studs and drill and tap new studs into the hubs.
I seem to remember reading that you could buy alloys that don't have any bolt holes, the holes being drilled by the supplier/manufacturer. See here as a random example. Those ones on that Trabant look like they are 14" rims if you compare the picture to a side view of a stock Trabant.
There were some Renault steel wheels lying around on our plot when we bought the house. They are actually 14" wheels but the bolt hole pattern seems to be the same as the Trabant. I haven't managed to try them on my Trabant as yet but that might be a nice project for the winter. I reckon that lower profile 14" 165 tyres should fit the rims and would probably just fit under the arches, assuming the offset is favourable.
Officialy, those 14 inch rims (Irmscher, produced by Ronal) were designed for Wartburg.
On a Trabant, you have to adapt some things to make them fit.
There were a couple of quite rare rims for the Trabant with the 4x160 bolt pattern. You can google for stuff like LTR, RW spider, Mattig.
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