Astronauts are allowed to take a personal preference kit (PPK) with them to space. The Wikipedia page for PPKs states how they are defined by the Federal Aviation Regulations as of January 2001. This implies that the definition might have been different before, and the PPKs of Apollo astronauts have different size and weight limits.
What were the limits for the PPKs of Apollo astronauts as far as weight, size and number of items go?
Partial answer - size
The standard Apollo PPK bag measured 8” x 4” x 2” (20.32 cm x 10.16 cm x 5.08 cm).
Reference: The Personal Preference Kit: What Astronauts Take With Them To Space
Weight - references not authoritative - collector sites
...the weight limit for a PPK was capped at roughly 1.5 pounds.
Reference: https://natedsanders.com/blog/2019/04/apollo-14-flown-ppk-personal-preference-kit/
...the PPKs had a weight limit of only half a pound.
