Are you talking about a lining with a fleecy/flannel feeling inside to it or just a fleecy layer that goes between the coat fabric & lining?

Yes, the interlining I used was thin, white, and fleecy/flannel-ish and goes between the coat fabric & satin lining. It was made specifically to make wool coats warm and wind-proof without adding a lot of bulk and weight. I basted the interlining to the wrong side of the wool of each piece, then treated the two layers as one, constructing the coat as if it were only one layer. I then sewed the satin lining as instructed in the pattern. The result was a very warm, dressy coat that lasted through several Chicago winters.

Armo & HTC both make a lightweight fleece, I think. It's about the same thickness as good craft felt, but lighter and fluffier.

I bought my HTC fleece at Joann's a couple years ago. They had iron-on & regular.

Denver Fabrics and Vogue Fabrics both carry thinsulate lining.

I am not familar with what you mentioned. A separate piece of any fleece I am aware of may make it too bulky. In Alabama, we don't have a need for extreme weather coats so we aren't exposed to much in stores. I am aware of a lining backed with this fleecy/flannel feeling fibers. It's just a heavier lining. You may find what you need online.

THINSULATE! That's it! And its little tag is everywhere, including the inside of a pair of gloves I've worn for years. I live near Milwaukee now, but Friday I will take myself right down the hwy to Vogue Fabrics, where they have it for $6.99/yd. Thank you, everyone.