Leaving aside the question of what a "jet rocket" even is, this seems to be the same company that sold the Polaris Nuclear Submarine. That ad was from 1967, so this may be a similar vintage.
Man, if only people knew to stockpile certain nostalgic toys. $5 in 1964 is around $54 today. If you could really get $1500 or heck even $500, that blows away both inflation and the stock market. Of course if you bought too many, you'd distort the supply/demand curve. But spread it out over a range of toys, and you're golden.