Can you direct me on how to acquire a US Capitol structure kit built or to be built??
You’ll have to scratch build it, and it is BIG compared to a typical HO scale layout.
Info from http://www.aoc.gov/cc/capitol/capitol_overview.htm
Today, the Capitol covers a ground area of 175,170 square feet… Its length, from north to south, is 751 feet 4 inches; its greatest width, including approaches, is 350 feet. Its height above the base line on the east front to the top of the Statue of Freedom is 288 feet; from the basement floor to the top of the dome is an ascent of 365 steps.
No lets convert that to HO scale:
… a ground area of 23.1 square feet…length, from north to south, is 8.63 feet; its greatest width, including approaches, is 4+ feet. Its height above the base line on the east front to the top of the Statue of Freedom is 3.3 feet; …
I’m sure this site has paper modelasavailable, but they would be much smaller than HO scale.