Help with finding parts.

Hello, I have several windows that only had these parts in them. None of the windows in the house have a complete system. I was wondering if you could help identify these parts. I have been told that they are from a block and tackle system. I did not see that on your website.

The show measures as follows

1 1/2" tall x 1 1/4" wide x 2/2" thick

The pivot bar measure as follows

2 1/2" long x 5/16" wide x 3/16" thick
To the first screw hole is 1 3/8".
Second screw hole 2"

Thanks