Get a solasfera or brellia. They have no/ little light leakage, hence ur diamond would definitely sparkle in diff lightings. You should be able to get up to an E color, VS2 and above, and definitely one carat. Most imptly, use the scope to see the diamonds for yourself. No point jus viewing the specs on paper. I've seen a one carat with F color and VVS2 but it jus seems normal to me, doesn't sparkle as well as those I saw in JP.
If you are satisfied with a super ideal cut instead of the solasfera and brellia, then I'm sure u can up the carat size a bit with your budget. I personally feel if u wanna get one carat and above then don't go lower than F color because the bigger the stone, the more obvious the yellowish tinge but since F is still considered under the colorless category, it's fine. Play around with the rest of the 3Cs. I would compromise clarity (since cant see the inclusions with the naked eye), and go for better color and size.
Basic designed settings are $550 for 18k gold and $900 for platinum. Unless you wan those more complex types for eg with side diamonds etc, it can go up to $2k depending on the setting design ( for eg Verragio) and number + quality of side diamonds
