I would suggest:
A Sales program separeted to the PURCHASING (PROCUREMENT) PROGRAM:
First put the program title, followed by its scope and its purpose,
then you go deeper in the different SOPs of the particular program, you put column withg respect to, who, when, where, how, and reference,
of course you use document numbers for document control purpose, I have a format, but not on me actually, just inform if this can help,
otherwise tomorrow or on sunday i will try to send.
for Purchasing, you will have as SOP a supplier approuval procedure, an incoming inspection of raw material if storage and receiving are merged.
hope that this can help,
kind regards,
Michael G