Hola,
After having had lotsa fun with the Polivoks VCF build, what the MB6582 really still misses is a "vintage" analog delay (moar saturation with increased delay times, "deluxe memory man" style), so I´ve looked into some diy analog delay projects...
Using the retro MN3005 bucket brigade chip would be my first choice (i know, there are modern alternatives, but the real thing with 15V headroom would be nice! ;-))
Now, there are some chinese sellers on ebay, but... you know...
Quest