WASHINGTON, March 22 (Reuters) - Billionaire Richard Branson’s cash-strapped Virgin Orbit is near a deal for a $200 million investment from Texas-based venture capital investor Matthew Brown via a private share placement, according to a term sheet seen by Reuters.Virgin Orbit soared 115% in premarket trading.A successful deal would be a major boost of confidence in the company that saw its market capitalization slump to a record low of $150 million on Tuesday from more than $3 billion two years ago when it went public through a blank-check deal.The negotiation comes after the satellite launch company said last week it was exploring strategic options and was in talks for funding after a cash crunch forced it to pause operations and furlough nearly all its staff.The two compan