Proteus model dac max534, AD7304

Hi, where can I download extra models/packages for components that are 
not contained in the existing library?

In particular I need the model for a max534 (or AD7304) quad 8-bit DAC 
with supply +5V and SPI-interface. (Dual and single versions are in the 
library amongst others, but not this)

Does anyone use this software who could help?