> I feel sure you will find what you are after in the digikey catalog.
> have a look at the 'bourns' resistor netwoks, at Fig G, dual term.
> They have a 10 pin device with zero ohms at the correct pins and what
> appears to be the correct R and 2R values in the resistor ladder.
> All you need it the 10K version for that DAC to PIC circuit.

There are two uses for R/2R resistor networks: line termination and
digital-to-analog conversion.  A network set up for the former will bias a
bunch of signals at 1/3 rail.  This may be used either to terminate
certain types of communications lines, or as part of a "poor man's"
multiplex LCD circuit.  Unfortunately, it won't be much use for the
latter application (D/A conversion).  As far as I'm aware, neither
Digi-Key, nor Mouser, nor Jameco have any SIPs of the latter type.