If you like ivories that much go for a pair of YBs, and maybe a pastel female. That would be within your budget, and you'd be able to produce YBs, ivories, pastels, pastel yellow bellies and normals, Then in a year you can get super pastels and pastel ivories, too.

Or you could find an 07 female YB and get another 08 male co-dom that you like for that price. Make combos first, then in a year you'd be able to go for the ivories. You have a ton of possabilities, just go for what you like the most.