After nothing more than a cheap fix to enable Fortnite playing!
Too late as usual; read-ahead mode was off!

From @bru's link, a 750ti has been validated. If a 750 ti will work so will a 1050 ti. Gigabyte, Zotac, and others make them so I'm sure OCUK can source them. Given the PSU, you won't want the OC versions.
BTW beware the GT 1030. There are two versions with the same name. Read this. TLDR: some cards have DDR4, others have GDDR5. You want the latter.