I may repeat something already said, but no time to read the full thread.
Last year I did the same (my daughter wedding), one shot of non-stop 47minutes 4K24p 8bit 4-2-2 ProRes 240MB/s gave 230GB. And easy encoded, more static subjects.
ProRes is a loss codec, also professional level (broadcasting).
Use of an SSD was in the process, clear HDMI out to an Atomos external recorder with a 2TB Samsung SSD Evo 850.
Lossless, as "RAW", I do not think available in a more or less comercial camera body, and also there are some codecs with the name RAW (!?), they do not record video RAW. But I hope without reading the specs, these RAW should give a very good quality anyway.
Check here:
https://en.wikipedia.org/wiki/Comparison_of_video_codecs
Just think, 4K is about 8Mpix and at 24fps and 8bit it means about 600MB/s (aka 4800Mbps). Want 30fps is about 720MB/s, double as 60fps is about 1.5GB/s = 12Gbps, somewhere more than the best performance of an commercial SSD drive (around 5-8 Gbps).
Just some professional equipment can do a 4K RAW, 24 fps or more.
If recorded on a "media card", SD or any else, this is not posible.
I would advise for a ProRes codec, similar ones (DNxHD or some RAW codecs do a similar job), high bitrate around 240MBps or more, best would be a 10+bit 4-4-4 (well, 4-2-2 will do it).
This is really high quality, as I said for TV broadcast (professional level).
You should manage something equal or a bit less, should be very good.