Swedish Glass Factories: Production Catalogues, 1915-1960 doesn't cover Kraka (just checked).
A better bet would be Orrefors, a Century of Swedish glassmaking.
It says that starting in 1960, kraka was brought into series production, and certain model numbers were produced in long series from 1960 to 1986, marked P or PU and the serial number. P449 isn't one specifically named. However 1963's output was numbered 444 - 450, so I'd guess from this period.
However, if you're talking about a very early piece signed Orrefors Sweden P440 Sven Palmqvist (probably just clear and white honeycomb with no bubbles) but no "Kraka" then this is a different story.
Any chance you could post a pic, or e'mail to me and I'll post (e'mail on memberlist).