Apparently unlisted, you can still get them in a digital bundle on PS4.
The standalone versions of both Uncharted 4 and Uncharted: The Lost Legacy appear to have been removed from the PlayStation Store at the beginning of Uncharted: Legacy of Thieves Collection.
Sony announced the Uncharted: Legacy of Thieves PS5 release date earlier today, and shortly after that, users at ResetEra realized that none of its founding games are currently available for purchase on their own via the PlayStation Store. Instead, now both Uncharted 4: A Thief's End and Uncharted: The Lost Legacy Digital Bundle You will need to buy it for 439 ₺ / 349 ₺ via
To be fair, it's about the same price as these two standalone games combined, so this is probably a move to combine store options; It may also have to do with the fact that players can pay a one-time fee to upgrade PS4 versions of both games to the Uncharted: Legacy of Thieves Collection. You can also continue to buy physical copies of both games. We've reached out to Sony for more information on this obvious delisting and will update this story with any response.
Meanwhile, if you own a PS5, it looks like it'll be worth your time playing with Legacy of Thieves Collection when it arrives in January (it's also coming to PC, although Sony has waited until next year to share more details on it). The next-gen package includes three graphics modes as well as full support for DualSense haptics and adaptive triggers.