Washing machines with agitators are available at retail outlets such as Home Depot and Lowe's. All are top-load models and include brands such as Whirlpool, LG and GE. The agitator style washing machines tend to be smaller, with less load capacity than those with impellers.
If searching the Home Depot site, searching "top load washers with agitators" only brings up models with agitators. The website has a compare feature where users can look at up to four washers at a time. The Lowe's website tends to lump all top load machines together, even if agitators are requested. The user needs to click on the models to see the specifications. A compare feature is also available.