As promised, pictures of the original crossovers.
From what I can gather, they're K500/5000 with 15uf (3x5 in parallel) and 1uf capacitors and 5MH, 5MH, 0.5MH inductors. Seems to match the schematic that was floating around on the forums a while back. 16ohm input.
The one from SN 490 (August 1953) has a replacement 1uf capacitor (I have the original). It's too big, but it works. Otherwise, they may be all original. They work, but the sound quality and coherence seem to ebb and flow, which I'm betting is from old caps. Simple things like a single instrument or voice sound great, but they start to sound messy when the music gets more complicated. Regardless, given their age, I'm impressed to get anything at all.