Yamaha CS80

I am trying to find a couple of parts through Digikey's website but I cant find them because i am fairly stupid.  I am trying to find IC21 and IC22 on the KAS board.  The numbers on the two 8 pin chips read 4558DV JRC 8011.    
I never know what portions of the alpha numeric part numbers I need to pay attention to. 

Also, I am looking for the part number for two other chips on Digikeys website.  They are the 4069P (not the 4069UBE chip) and 4050P chips on the KAS board.  Those are IC6 and 7 on the KAS board.
I am making a pretty large order on digikey and would like to find the right part no. for the three components I listed above.  

Can anyone spare some time to help me out.

Thanks,
Steve


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