If you don't have enough in stock, I'll just take what you have.
If you don't have enough in the back, could you just give me what's available?
ーIf you don't have enough in stock, I'll just take what you have.
「在庫が足らなかったら、あるだけいただきます」
don't have enough in stock で「在庫を十分抱えていない」
ーIf you don't have enough in the back, could you just give me what's available?
「在庫が足らなかったら、可能だけいただけますか？」
don't have enough in the back で「（店の）奥に・裏に（在庫を）十分抱えていない」
これは実際店でいう場合に使えます。
ご参考まで！
カナダ 
