....but if you want the raw scan I can upload that to oneDrive. It's too big to upload here
Yes please!

U10 looks like a dual optocoupler, could possibly be replicated with two discreet modern optocouplers?
[EDIT] I'm gonna say this one is a dual channel open-collector optocoupler.
The Broadcom/Avago HCPL-2630-000E and HCPL-2631-000E (latter has better common mode transient immunity) are pin compatible, see
page 5 of the datasheet.
I think the Vishay VO2630, VO2631, and VO4661 are all worth checking out too, and they are cheaper than the Broadcom part.
(The three parts have different common mode transient immunity and propogation delays, I don't think these specs are overly important in our application)
U11 is something funky, is that a NAND gate with an optocoupler on one input? Maybe something like an
NTE3087? I wonder if there are modern equivalents?....
[EDIT] How about a
6n137? It looks pin compatible from a quick glance at the schematics...
Seems the 6N137, VO2601, and VO2611 are all pin compatible here too.