I'm not sure if discontinued is accurate. That listing is for the CSO-300N, Cuisinart.com has the CSO-300 discontinued, but has the CSO-300N1 on the regular part of the site with no listing of just the N. If the N1 is a newer version, it unfortunately does not appear to have an increased capacity (I admit to sometimes longing for the french door Oster largely because of its size). I do find it interesting that the click through merchants do not include Amazon, although that might not mean anything as they don't hi light a link to Amazon for another oven I know is carried there either.
https://www.cuisinart.com/products/toaster_ovens/cso-300n1.html