discontinued chips

[Mr disco]

Hi all

Forgive me if this is an idiotic question, since I'm brand new to the list
and to synth DIY in general... That said, does anyone know what would most
closely replace either of these chips?

uA798TC
MC3401

The first is some sort of dual op amp (not the same as a 1458, I don't
think) and the second is a quad Norton amp.  Neither of them seem to be
made anymore.  Can they be replaced with standard chips?  Is there some
sort of universal cross-reference for discontinued chips?  Any help on or
off the list would be appreciated.

Thanks,
Mr disco


+--------------------A Mr disco Production--------------------+
|   "Go forth and multiply..." -Yamaha CS1x owner's manual    |
+----------------------vcf at mindspring.com---------------------+