let (someone) buy, make (someone) buy
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.
同じのを買わせてちょうだい。
Please let me buy the same one.
別のを買わせてもらえるかなあ。
I wonder if I could buy a different one.