There is
International Historic Films, who offer quite a wide selection of Third Reich cinema in their catalogue.
I've seen and/or own some of their Third Reich releases and found them all watchable, though print quality and transfer method seems to vary, and I think most titles are DVD-R, unless that has changed since I bought
Ohm Krüger (which also has a light strobing effect throughout). A few are taken from 35mm and I think all their releases have contextualising extras, quite extensive in some cases. R Dixon Smith (who used to work for Eureka/MoC when he lived in the UK) provides written essays for some of their releases.
IHF is at least a bonafide company who, in my experience, deliver what they promise, and I believe they try their best within their limited means.