Missing - the Last Piece

I guess I can say that putting together my top for Bonnie Hunter's Allietare Mystery Quilt is a bit like assembling a jigsaw puzzle!  I lay pieces out, stand back and think something like "That doesn't fit there!" or "I need a piece with a darker red".  I have sewn half of the top top together and am loving it, though.  Today I was working on laying out the last half, and I find that I am missing one of these units:

In fact, I think it may be this very unit!  I know I turned the half that I sewed on wrong, but maybe I set it down somewhere in my sewing room instead of with the rest of the units? I know at some point I had them all because I counted.  I keep hoping it will turn up, but if I don't find it soon, I will have to make a new one!

Here is the first half of my quilt:

I do like this one very much, even though I never would have thought I was a fan of red and gold.  I also love the grey in it.  So pretty.  Actually the colors makes me think of my Junior High school.  Our colors were maroon and gold.  We all thought it was a pretty yucky combination then, but what do Jr. High kids know?

I think I might finish putting my blocks together tomorrow.  Then I have an idea for my gold border.  I love the fabric, but I don't know that it will work on this quilt so we'll have to see what it looks like.  But first I will have to find that last missing piece!