買わせて

let (someone) buy

→ 買う
買わ buy + せ causative + て Imperative
verb Rare #40,487
let (someone) buy In requests, often means “let me buy.”
JA: これを買わせてください。
EN: Please let me buy this.
Conjugation of 買う
Imperative
買え買わせて

同じのを買わせてちょうだい。

Please let me buy the same one.

買わせてくれ

Let me buy it.

— デッド・ドント・ダイ (2019)

別のを買わせて下さい。

Please let me buy a different one.

別のを買わせてもらえるかなあ。

I wonder if I could buy a different one.