recommnedations for using a DDS with the Universal Receiver)

There is no specific kit designed for DDS operation.
You should choose one of the VFO or VCXO kits based on IF requirements for the DDS application.
The following parts/items must be installed for DDS operation:

L1
L3
T1
C3 12 MHz Receive Frequencies and below
C7 if Frequency Counter is used
C12 100n coupling cap between DDS and Mixer U1
C14,15,16,17
C20,21 normally 120pF NPO
X1,2,3,4 Matched IF crystals