The condition in this statement is possible and not unlikely: it is possible that there isn't another option; I don't think that corresponds to "second conditional".
The sentence you propose isn't what you would say to your teacher, but it could appear in a sentence about what you said to your teacher.
In speaking to your teacher (direct speech), you could have said
If there isn't another option, I would be interested in hybrid courses.
In telling someone what you said to someone else (reported speech), you could say
I told her if there wasn't another option, I would be interested in hybrid courses.
The backshift of "isn't" to "wasn't" happens in reported speech. That backshift is optional, so you could also have said
I told her if there isn't another option, I would be interested in hybrid courses.
Google Books Student's Introduction to English Grammar "backshift"
"In fact, even with preterite reporting verbs backshift is often optional: you can keep the original present tense instead of backshifting it.