Things are looking up for the dual layer pricing. You can now get 3/10pks at sams club for $59.86 as their everyday price. I'm not sure when this prices went down, but I bought them a few weeks ago for around $76. Take a look here:
Went looking further around at their media and they have sony dvd+r 8x MIJ. They come as a 75pk for $25.73. Warning though you do have to look through them because they're a 50pk+25pk and usually the 25pk is MIT. At my local club half of them were MIT/MIJ and the other half were MIJ/MIJ.