LM13600

[Jim Battin]

I'm trying to build a Korg MS-20 Dual Filter (From the cookbook :).  I
allready have most of the parts, however I am having troubling finding
an LM13600.

The LM13600 seems to be hard to come by (or atleast in the US). 
Digikey, Jameco, and mouser don't carry it (pios.com does however.. but
You have to call about getting it in stock).  Is there a op-amp with
similar specs that can be used in its place? (LM13700?).