A novice needing help looking for a vintage cushion diamond

[desperateforhelp]

First off, I just wanted to thank the PS community for this amazing resource on diamonds. For a novice like myself making his first and probably most expensive diamond purchase this been an invaluable tool. I've had the opportunity to read a lot of the earlier posts and view at lot of the movies regarding diamond education, but I now find myself more flustered than ever when looking for the perfect engagement ring for my girlfriend. I've been to multiple local B&M jewelers in the Boston area, and queried multiple online search engines, but I don't want to purchase a cushion without at least seeing detailed pictures of the diamond.

I know I want to get her an vintage/antique looking cushion, and I love the AVC's from GOG but I find that there doesn't seem to be any diamonds within my budget window. Specifically I'm looking for

Carat: 1.7Ct+
Budget: ~12.5K (stone only not setting)
Color: H+ (Maybe I)
Cut: Cushion (chunky faceted - not icey)
Clarity: SI1+
LW Ratio = 1 - ~1.1

I guess I'm looking for an "eye-clean" cushion diamond, with chunky/vintage facets, that is maximized for light performance, that faces up as large as possible given my budget.

Perfect but just out of reach: http://www.goodoldgold.com/diamond/8209/
Just a touch to small and looks a little "busy" compared to above: htps://www.engagementringsdirect.com/DiamondCushionDetails.aspx?Item=55

Does this stone exist, and can I find it?

Please help!