Reference
Hartill GCC : pp. 21, 105, 144, 147, cf Figs 2.61, 2.810 - 2.813, 2.875
Note:
This coin, with its clearly moulded characters and broad, well-defined rims, is quite unlike any of the coins with the legend Thái Binh Thánh Bảo (or Tai Ping sheng bao) illustrated by Hartill (GCC). It differs from these and from all the coins described by Thierry (CMV, CMVS) and on Zeno.ru in having the seal script character 寶 of a distinctive and unique form.
I have applied a provisional date range from c. 1540 – c. 1800 to cover the likely maximum time period during which a coin with this legend could have been produced in Vietnam and be likely to have reached the collection of Kutsuki Masatsuna while he was actively studying numismatics. Kutsuki Masatsuna's collection had at least three examples of this coin type: HCR 58854, 58858 and 58862.