The Browning website is one source. Browning, Sporting Arms of Distinction by Matt Eastman covers up unitl 1992.
Besides a number of books published on Browning, and some of the gun collector forums (google Browning collectors) you might start with Browning. They have a website, and are still in business making very nice rifles, shotguns, and pistols.
Information not in the public domain.
Browning Automatic Rilfe
Japan
Yes
No way to answer without more information on both rifles.
Embellishment
As far as I know browning did not have any firearms made for them in australia.
Depends on the specifics of the one you have.
Rifles can be purchased from the manufacturers such as Browning or Smith & Wesson. Rifles can also be purchased from third-party stores such as Amazon.
Browning has made centerfire lever action rifles in various calibers over the decades.
On the webste for Browning firearms, under customer service.