Looking for missing parts for Omega Medicus cal 23.4SC

[dezro]

Hi everyone,

I am looking for some help in sourcing the missing parts for a vintage Omega Medicus that I've inherited.
It is a cal 23.4SC, I don't know much about vintage watches, but I would like to have it restored if I could source the missing parts, without paying silly money.
What's needed (please correct me if I'm wrong) would be the pivot / centre second pinion / second pinion cock / seconds hand.
On another note, I guess the case back is not an original, it is only stamped with gold hallmark and 'ML', plus a 5-digit serial number.
Could someone advise where I could try to find the missing parts? Any other information on the watch would also be appreciated!

Thanks,
Dan