Can anyone recommend a good source for hi-res HDRi skies. Ideally free but I am willing to pay. I've had a look at the links to some of the HDIs on this forum but a lot of them are not that good low-res images. If anyone is using some commercial images that they would recommend then that would be brilliant as long as they are not too much money. I am only a hobbyist and don't have hundreds to spend on HDRis.
(HW) Intel i7 2600k, 16GB DDR3, MSI 560GTX ti (2GB) x 3
(SW) Octane (1.50) Blender (2.70) (exporter 2.02)
(OS) Windows 7(64)