In search of help or direction on Altec A-7 500 16 Ohm Magnificents.

I am looking for anyone who can lead me to the schematics for these 300 Hz. Crossovers and or someone who can build me new crossovers.  I have been restoring a pair of these and they look and sound beautiful but now that I have taken them this far I would love to take them to the next level.

Thanks in advance for any help or direction here!