[sdiy] Attempting Korg MS-20 clone as first COMPLETELY diy project... Questions

[ordeish at aol.com]

 Hi all. I have been doing projects from boards purchased, like CGS, etc. But have decided to try my hand at breadboarding my own project, the ms20 filter. I know its been done to death, but not by me, and I am on a low budget and want it myself. 
 Anyway, the questions I have is... In the schematics it calls for the 4558. Very newby question, but I see many varieties of that chip. Which do I go for? 
 I have already purchased the lm13600, so that is good to go.
 It also call for a798f. For the life of me I can't find that anywhere!
 It also shows 2 2sc945 transistors and mentions them as (selected) and says K*2. Does this mean matched? 
 Sorry for the very newbie questions, but, I just don't know the answers, and don't know where to look!

Thanks

Ed
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