A sale on March 16-17 in San Pedro, CA includes lots of typewriters, especially postwar office machines but also plenty of portables and some older machines (such as an Oliver 9). I expect it will be a good chance to get an affordable Selectric, KMM, SG3, or other excellent writing machine.
Go to this page and scroll through the photos until you start hitting the typewriters.
Right now they don't provide any details on exactly where and when the sale is. But you can send them an e-mail through their site, or visit them on Facebook.