I inherited two quilt tops myself and used a regular cotton batting from the fabric store. Found a backer fabric that worked: a solid gold with a small calico-like pattern, barely visible.
It was hard to match the purple in the second one but I managed to find something compatible for borders.
The backer is an intense purple calico with shades of other purples that I think worked great...
And because the tops were old I quilted out the wazoo. by hand. In spite of that, there were tears before I finished but only a couple.
These were both from 1935.
My apologies to the professionals who probably think I did not do them justice, but we intend to use them until in shreds...
Also, I saw the Gees Bend Quilts and have a different opinion of what quilting is. Different from my old views that is.