Not unless it is a special order.
No way to tell from the sn. You will have to contact Miroku
Possibly if it is a Browning made by Miroku.
The letters NZ in the serial number indicate that your Miroku made Browning was made in the year 1991.
Miroku guns made under their name does not have serial info published. Winchester, Charles Daly and Browning have all been made by Miroku in the past. Do you have a model?
Msterials used were similar to material used today- metal and wood. The earliest firearms were made of brass for the barrels, and wood for the stocks. Later guns were made with barrels of iron, and later steel.
Around about 1984
==Miroku Firearms Web Site == http://www.miroku-jp.com/gun/
Wooden barrels are made by a Cooper, and that is largely a hand craft. Steel barrels are made in a sheet metal shop, as this workplace is called, and this process is fully automated.
Miroku 800W have a value of 950,00 euros, in very good shape, near 95% at least. Some opinions say that is a little heavy, but the steel barrels is very good and the dispersion of the shot is very homogenius, there are news models, but this one have about 28 years.
Someone who makes barrels is iether called a barrel maker or cooper. Barrels are made from only one type of cooperage. Barrels are also traditionally made of wood staves.
No published sn data I know of