Your description sounds like marked wholecloth tops I have seen in Quilt shops in Pennsylvania. I was interested because they looked like they were hand drawn which appeared unusual. I ask the clerk about them and the source. She told me they were hand marked by an Amish quilter who was well known in the area for her whole cloth designs. She went on to say that the designs could be attributed to specific quilters. The quilts were usually custom marked for the customer but the shop had been able to get some to sell. Your tops may be from such a source. Perhaps someone will have more accurate information about your tops.