送我幾個 Send Me A Few As Well
八戒看見，就叫道：「老壽，有火棗，送我幾個吃吃。」壽星道：「未曾帶得，待改日我送你幾斤。」八戒看见，就叫道：「老寿，有火枣，送我几个吃吃。」寿星道：「未曾带得，待改日我送你几斤。」
逐句解 Line by line
Bajie saw it and called out, "Old Longevity, if you have fire-dates, send me a few to eat."
老壽 — he shortens the god's title to a nickname, the way you would call a man named Longstaff "Longy." 火棗, fire-dates, are a legendary immortal fruit paired in Daoist texts with the 交梨, the crossed pear. Bajie has correctly identified what he just watched and wants some.
The Longevity Star said, "I did not bring any with me. Another day I will send you a few catties."
未曾帶得 takes dé. 幾斤, a few catties — about half a kilo each. He has gone from three dates to several kilos, which is what you say to somebody when you have no intention of doing it. The novel does not record the delivery ever arriving.
Bajie asks for the thing that has just cured a king, out loud, in front of the court, immediately. Nobody else would and he does it without a flicker.
The god's answer is a brush-off dressed as generosity, and the unit of measure gives it away. Three dates were a serious gift; several catties is what you promise when the promise costs nothing.