好的，我們約７點，晚點見。

好的，我们七点钟见面。再见。 This would probably an accurate translation of what you're trying to say. Joan's answer reads, "Okay, we'll arrange to meet at 7. See you later" (although 晚点见 is more along the lines of "to meet at a later time" instead of "see you later"). Your original answer actually reads as, "Okay, we ruler-o'clock will. See you in a bit." Yes, you used 尺(ruler) instead of 七(seven) =)

好的，我们约七点，等会儿见。