SpaceX (SPCX) shares are "cheap and getting cheaper," Morgan Stanley analyst Adam Jonas said in a note Sunday.

The shares have hovered around $150 per share since early August, and at $159, investors can take advantage of an opportunity to buy shares that, "while expensive on any trailing metric, look unusually cheap on the forward," Jonas said.

Price: 166.09, Change: +7.13, Percent Change: +4.49