I'm attempting to create a RH trilogy ring using 2X .30 round transitional diamonds as my side stones (stones from grandmothers ring) and a gemstone as the center. I love the Lily round trilogy ring by. I don't know much about gemstones and costs seem to vary greatly online but basically I'm looking to source a round stone that's approximately 7mm in size. I'm open to various gemstones but tend to gravitate towards blues, purples or even yellows. I'm clearly not looking for the most expensive stone and want to understand if I could get a decent stone in the size I want for no more than $1000. Is that even possible or am I totally out of my mind?