Miroku and original Win 1873 barrel shank size/ thread pitch?

[LeftyLarry]

I am plotting to add some barrel length to my Miroku 1873 and was wondering if an original barrel would fit? Also, does anyone happen to know what the dimensions and thread pitch of an original Win 73 is? I haven't got my existing barrel off yet but intend to get under way pretty soon.

Thanks
Lefty