According to Comic Natalie, Animate will sell a pair of glasses which reproduces the ones of Shimura Shinpachi
from March 15th. The price is 3,150 yen ($40). The glasses are called "Shinpachi's main body".
Picture of Shinpachi (glasses)
The 43rd volume of Gintama comic book will be released on February 3rd.
Source: Comic Natalie