Classic TV - Tales Of Tomorrow_- "Youth On Tap" (1952)

A man named Jeff definitely has his share of problems: his truck has been stolen, his girlfriend Kitty is impatiently waiting to be married, and he only has one week to come up with a thousand dollars to buy a gas station with so he can earn money. When a mysterious Dr. Platan shows up offering the thousand dollars for a pint of Jeff's common blood type (type A), Jeff accepts at first, but then has doubts...
https://www.imdb.com/title/tt0717095/plotsummary?ref_=tt_ov_pl

This video is in the Public Domain.