Vintage Regency Cashmere Union Made US Black Long Coat Button Overcoat Size 4

Please see photos/last three showing the inside lining, wear to inside left shoulder. Measurements are shoulder seam to shoulder seam:16”, armpit to armpit:18.5”, sleeve length 21”, shoulder to hem:44”. No tag indicating actual size or materials. 5 silver colored buttons reaching beyond waistline. No damage to outer shell.