I know you said you don't want a pre-loved ring, but all diamonds are already reused unless they are custom cut.
I think these options below would be a great value for your money.
Plus they have a little bit more uniqueness than a basic solitaire does.
GIA CERTIFIED OLD EUROPEAN CUT DIAMOND ENGAGEMENT RING I SI1 PLATINUM VINTAGE OE
Elegant and full of brilliant sparkle, this vintage engagement ring’s classic design is crowned by a stunning GIA certified old European cut diamond. The beautifully white and 100% eye clean 0.51ct diamond is hand cut with wide facets that deliver dazzlingly bright sparkle and vivid fire. The...ivyandrose.com
https://ivyandrose.com/products/gia...ent-ring-platinum-old-european-cut-vintage-er
That's a lovely option @ elizat. Johnjo56 what do you think of it?