3+ ct Radiant Cut Diamond X-Z Color SI2+

I'm looking for a 3+ ct square Radiant cut diamond that's in the X-Y-Z range and SI2 or better and no clarity enhancement please. I prefer a GIA cert but it's not required. Very good to excellent cut and proportions are important. I'm looking for the best bang for the buck but please don't ask what I want to spend. Who ever comes up with best value is who I'm going to buy from. I'm a serious buyer and want something within the next couple of weeks so please let me know what you've got.