I would go with a lemon blast...opposite sex as your bumblebee. Those seem to go for well under $1,000 now.

Bumblebee x Lemon Blast can produce...

Spinners, spinner blasts, killer blasts, killer bees, super blasts, lemon blasts, bumblebees, super pastels, pastels....and maybe a normal.

If you want to do something a little different, you could get a Pastel Vanilla for $750, a Super Vanilla for around $900 - both would work really well with the bumblebee and the butter.