If it were me I would save my pennies dudes, not by much though for £300 450 you can buy some very well regarded DACs that are a step up from the 203. Perp Tech P3A, TAG DAC 20, MF A3.24, CAL Labs, Micromega there are loads FWIW Ive read of 2 users with CD72s that have tried DAC I can recall, one tried a 203 funnily enough and liked the 203, another audio user I know had a CD72 and did a A/B comparsion with this system : Sony DVP-NS305 DVD Player / Rotel RDP-980 DAC and kept the DAC and sold the CD72. The Rotel DAC IIRC was £200 off Ebay :
Just to frustrate CJ, i would agree with him on this. The 203 is too old tech wise to give the sort of improvements you would want. If you can get an MF A3.24 for around £300 though you would be lucky indeed!! The RDP's a good bet at a better price. I would refer to CJ on this, but a DPA bigger bit might also be a more sophisticated bet, but still a little dated.