He is commissioning you to make him a replca of an old tied quilt? Why can't you just copy the pattern as shown in the pic, using cotton fabrics and a good muslin for backing...maybe two layers of cotton batting would give the "heft" he wants..since you have a longarm you could mount the layers as per quilting, but tie with yarn instead. Using "old, washed" blankets for batting and miscellaneous types of fabric just sounds cheesy to me.....but if he's willing to,pay for that rather than new....jmho