Beautiful! You did excellent with those blocks in choosing a pattern that worked with odd sizes.
Several years ago I made a quilt for my youngest son's 17th birthday and wanted to back it in minkee. But, had the same problem as you do. I asked the store owner if she could find me some brown minkee and she did.
Can you buy from Joann's online? They have different colors. They don't call it minkee though. I just bought 5 yards of black minkee like fabric from them before Christmas.