Yes, the sentence is correct. In that sentence "should" means "if".
It's interesting, isn't it? If you think of "should" meaning "ought to", then it doesn't make much sense, but if you think of "should" being similar to "would" this usage might be easier to understand....?
I think some modals have 'original' meanings in English.
For example, "will" means "wish" and "desire". When you say
"I will do this tomorrow."
you mean
"I wish to do this tomorrow. (I wish, so it will be done)"
This is another example of mine :
"It is going to rain."
means
"Clouds gathered, it became darker. It will probably go and be a rainy state."