Most bees acquire mercury from mercury switches, if the truth bee known, since these switches are used in so many applications
The time tested method for producing mercuric chloride is to dissolve mercury in an excess of sulfuric acid, crystallize the mercuric sulfate, and heat it with aqueous sodium chloride, sublimating the mercuric chloride, the source of it's common name,
corrosive sublimate This and many other methods are covered here, like much of what you've posted, if you check you'll see there's thousands of posts
Lots of bees work with mercury at home, hopefully without contaminating the environment, techniques for avoiding that are posted here also
We even have methods for creating and handling hydrogen sulfide posted, but that's something we don't recommend, since there's no way to make it idiot proof
Much more could bee posted on the subject of mercury, but there's not a great deal of interest in industrial methods, analytical procedures or other chemical data since they're not usually adaptable to home use
We appreciate attempts to inform the newbees, but scientists should always bee prepared for a critic, there's many buzzing around here waiting to pounce