Nope, Miroku had nothing whatsoever to do with making the Winchester 101, the correct answer on the the 101 is in your statement though. Olin(Winchester) partnered with Kondensha(Nikko) to produce the 101, model 96, 23 etc
Winchester Repeating Arms Company -- Its History & Development from 1865 to 1981, by Herbert G. Houze. 511 Pages. Copyright 1994 and 2004 by Herbert G. Houze. Krause Publications. ISBN: 0-87349-786-4.
"After reviewing all possible locations (Austria, Belgium, Germany, Great Britain, Japan, the Philippines and Spain), it was decided that Japan offered the best possible venue. Olin-Mathieson then commissioned a survey of all the arms manufacturers operating there to determine which one would be most compatible with the Winchester company. Furthermore, as many of those firms were already producing superimposed shotguns, Olin-Mathieson authorized a second study to ascertain which one might be best suited to the American market.
Ultimately, this research was to result in the selection of Miroku Limited in the Tochigi Prefecture as the best possible candidate. Shortly thereafter, Miroku and Olin-Mathieson agreed on a working relationship, and a new company called Olin-Kodensha Limited was established in 1961 to manufacture shotguns bearing the name Winchester. "
Miroku didn't have anything to do with production, they part-owned and helped set-up the line in the plant, the company also produced the Nikko line of guns. When Olin pulled out in 1988 the plant became a parking lot.