For this reason we are going to say attributed to Sevres. For sure French in origin and antique.
As you can see there is gold rub. Both have rough production glaze marks on back side. Both bust have similar production glaze marks.In addition, Marie has some chipping around bottom base, see photograph. Louis looks like it has a very very good restoration to base back and side rim. This really is hard to notice.
However, we did detect a few white streaks on bottom base as shown in the photograph. This is what led us to the extremely good restoration.
Minor production porcelain separation lines. Marie stands approximately 11 1/2 inches tall. Louis is approximately 10 3/8 inches tall. Bottom base is approximately three and three-quarter inch square.
They really are quite fabulous. The item "Antique French Sevres Porcelain bust of Louis XVI and Maria Antoinette" is in sale since Sunday, November 1, 2020. This item is in the category "Antiques\Decorative Arts\Ceramics & Porcelain\Figurines". The seller is "cheekyshopper1700" and is located in San Diego, California. This item can be shipped to United States, Canada, United Kingdom, Denmark, Romania, Slovakia, Bulgaria, Czech republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Australia, Greece, Portugal, Cyprus, Slovenia, Japan, China, Sweden, South Korea, Indonesia, Taiwan, South africa, Thailand, Belgium, France, Hong Kong, Ireland, Netherlands, Poland, Spain, Italy, Germany, Austria, Bahamas, Israel, Mexico, New Zealand, Singapore, Switzerland, Norway, Saudi arabia, United arab emirates, Qatar, Kuwait, Bahrain, Croatia, Malaysia, Brazil, Chile, Colombia, Costa rica, Panama, Trinidad and tobago, Guatemala, Honduras, Jamaica, Barbados, Bangladesh, Bermuda, Brunei darussalam, Bolivia, Ecuador, Egypt, French guiana, Guernsey, Gibraltar, Guadeloupe, Iceland, Jersey, Jordan, Cambodia, Liechtenstein, Sri lanka, Luxembourg, Monaco, Macao, Martinique, Maldives, Nicaragua, Oman, Peru, Pakistan, Paraguay, Reunion, Viet nam, Uruguay, Ukraine, Cayman islands.