You obviously didn't read the first page. . .

Contract one or more refineries or natural gas producers to procure about 1,000,000 to 1.25 Million Metric tons of selected sulfur compounds  . . . Canada would be a perfect source. . .they have an over abundance of the stuff. . . [link to www.nrcan.gc.ca]

Finally, contract an air operations firm to retrofit and fly a few  aircraft at about $1.25 Billion 2008 dollars per year ( according to  . . .lines 138 - lines 143 and graph on line 528 in [link to climate.envsci.rutgers.edu] according to this paper the required amount of sulfur aerosol can be delivered easily by dedicated flights by only [. . . line 528] using nine (9) KC 10 Extenders or equivalent aircraft, each flying three (3) flights a day, 250 days per year. . . . 27 flights per day).

:C - Gun:


They could easily operate from one or more locations in the world . . . Canada would also be perfect for the air operations . . They are also close to source of the compounds needed and have remote airfields, as well as close to the lowest altitude for the stratosphere on the globe  around 36,000 feet. . . .where injection would the most effective cost effective. . . .
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NOTE:  The altitude of the bottom of the stratosphere varies with latitude and with the seasons, occurring between about 8 and 16 km (5
and 10 miles, or 26,000 to 53,000 feet). The bottom of the stratosphere is around 16 km (10 miles or 53,000 feet) above Earth's surface near the equator, around 10 km (6 miles) at mid-latitudes, and around 8 km (5 miles) near the poles. It is slightly lower in winter at mid- and high-latitudes, and slightly higher in the summer. The boundary between the stratosphere and the troposphere below is called the tropopause. [link to www.windows2universe.org]
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Commercial airliners typically cruise at altitudes of 9–12 km (30,000–39,000 ft) in temperate latitudes (in the lower reaches of the stratosphere).[2] This optimizes fuel burn, mostly thanks to the low temperatures encountered near the tropopause and low air density, reducing parasitic drag on the airframe. It also allows them to stay above hard weather (extreme turbulence).
[link to en.wikipedia.org]
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