Use a 1:10 scale making the court 93.6 x 43.2 inches.
How can I go about this?
Counter-question: What does it matter? In AE you strictly deal in pixels, so as long as the relative proportions are retained, AE couldn't possibly care less if the art was created at a specific scale and you can scale it to fit any time using continuous rasterization without quality loss. You're creating a problem where none exists. You can work at 1/100th scale in a standard A4 document and as far as AE is concerned, the result would still be the same. really, you are creating a problem by overthinking things...
Use any vector drawing program other than Illustrator: User-defined drawing scales has been standard fare for decades.
Hey guys. Thanks for all the suggestions. I wound up making it 936px X 423px, where px would represent in. Turned out great.
To answer the question as to why it matters with regards to AE, you are totally correct. I just wanted the look of the court to be as accurate as I could get it as I've drawn things before that looked right but when viewed from different angles didn't.
Here's my creation...