MembershipEndDate not exposed in Search Builder
It's present, but for who-knows-what-reason, it's labeled "Membership Expiration Date" in Search Builder.

However, before you go celebrating, in 4.7.25 there's a bug CRM-19998, which says, "Membership start / end date have no effect in Search Builder".

The GOOD news is that a fix was written for this.  It was merged yesterday.  The bug tracker says it's in Civi 4.7.27 - but next month is going to have a slightly unusual version release, so I suspect this is actually coming in 4.7.28, on December 6, 2017.  If you need it today you can manually apply the fix.