While the Surface Pro 3 has just been released, the latest Windows RT version is still the Surface 2. It is powered by Tegra 4 and contains 2GB of RAM. It also cannot run anything, unless it comes from Windows Store, it is a Windows Update, or it is a website that runs in Internet Explorer 11. If what you are looking for is Microsoft Office 2013 RT (included), Netflix, Halo: Spartan Assault, and so forth, then all Surface 2 models are currently reduced in price by $100 at the Microsoft Store.
Of course, the launch of the Surface Pro 3 without a corresponding Surface 3 suggests that this sale is a way to clear up-to year-old stock for a product refresh. In January, there were rumors circulating that a Surface 3 would appear with a Tegra K1 processor. Of course, with the first two RT-based Surface tablets containing Tegra SoCs, that could just be pattern recognition (rather than concrete information). Other rumors claim that Microsoft is interested in Qualcomm's chips, if only for a "mini" variant.
Either way, you can get a Tegra 4-powered tablet for $349 USD (32 GB), $449 USD (64 GB), or $579 USD (64 GB with LTE from AT&T). Previously, they were $449, $549, and $679, respectively.