Barry Bernal, the actor playing 15-year-old Willie, was 26 years old when this episode aired.
Soldiers serving in foreign lands and falling in love with local women has been predictably happening for millennia. During the Viet Nam war the United States was the only participant without a method for soldiers to bring back their native loves or their children. Even if a soldier could get permission to marry a local woman ( very, very unlikely) he still could not bring her home.
The $500 that Willie was offered comes out to $1,031.05 in 2019.
Chloroform, anaesthetic, put fire to it it will blow believe me. The writers almost certainly intended to say 'ether' not 'chloroform'. Chloroform is rated as nonflammable and hasn't been used medically in the last 100 years. Ether was used as a general anaesthetic back in the days when blowing up your patient was seen as merely unfortunate. The use of insanely flamable ether when the only light was oil lamp, gas light or candle made some surgeons nervous.