If you would consider a used stone on the secondary market, Jewels by Erica Grace has a 1.02 round in a squared halo for $3550.
It's the second ring on this page: http://jewelsbyericagrace.com/modern_and_estate_jewelry_page_2
It's the second ring on this page: http://jewelsbyericagrace.com/modern_and_estate_jewelry_page_2