[TenTec] omni 6+/ power issue

[Stuart Rohre]

You can google for discontinued chip numbers.  Some companies are in the 
business of making obsolete types of semiconductor families, such as 
Lansdale Semiconductors.
The real rub might be on ROM chips where the manufacturer no longer has 
a programmer to support them.  But, with some effort, you can work 
around those issues as well.

A number of companies sell discontinued parts.

-Stuart Rohre
K5KVH