Amazon offers Prime members Steins Gate: Complete Series Classic Blu-ray for $27.49 with free shipping. (Non-members can spend $35 or more to qualify for free shipping; otherwise, shipping costs $4.98.) That's the lowest total price we could find by $8. This eight disc set includes bonus features like episode commentaries, Akihabara map, textless songs, and the U.S. trailer.

Note that although it's temporarily out of stock, it can still be ordered at this price for delivery when available.