AFAIK, they were using knock-off Knowles BA drivers produced by Bellsing in the Solaris. Not clear who makes the planar driver inside the Supermoon. Some claim it's the same driver as in the 7Hz Timeless, considering extremely similar tuning and physical characteristics (albeit CFA put some extra effort in obfuscating the driver properties by representing them in unconventional way, so it's harder to compare them directly to ChiFi planar IEMs).
Also, interestingly, they do not mention 2 micrometer thick diaphragm anymore for the updated and cheaper chromatic series Supermoon, just a custom 14 mm driver. I guess 'custom' is to explicitly distinguish from those you can buy on aliexpress. Overall, if they can easily cut the price by a few hundred USD and still remain profitable suggests that the profit margins were huge from the start.
Nevertheless, those who owned both Supermoons and competing Chifi planar consider the former to be vastly superior, which can also be explained by a much better acoustic design of the cavity and different driver tuning.
So in the end, if CFA used their IP to obtain superior sound quality to the competition it makes sense they charge more for it. It's an open market: if someone can achieve the same performance for 300 USD, then no one will pay the Supermoon price.
I personally was hesitating between Audeze Euclid and CFA Supermoon and bought Euclid, mostly due to a huge discount. They sound very different but both technically impressive.
, btw what shell are you going to be using for this?
