For order #30879, the total payment was $1,183.81. after 30% restocking fee applies, which means your remaining store credit is $828.67.
The total price for the XR1921 ring in 14K yellow gold size 7 with the 704503113 stone is $972.88 ($704 for the setting + $268.88 for the stone).
Therefore, after applying your store credit, there will be a price difference of $144.21 ($972.88 - $828.67).