Bavarian Hefe - which hops?

I am about to brew a bavarian style hefe from a simple recipe of:

5 Gallon batch (late extract addition)
6lbs Muntons dry wheat extract
Wyeast 3068 Weihenstephan Weizen

Problem is, I don't have the hops called for in the recipe. I do have an unopened package of Galena or about a half ounce of Perle 5.7aa pellets, which puts me short of my target IBU of about 15. I was going to add some cascade leaf I have just to bring up the bitterness to where it should be, but I want to make sure this won't impact the bavarian style flavor I am shooting for.

So, should I use Galena or the Perle/Cascade combo?

Cheers!

Use a German Noble aroma hop and keep you IBU's low (8 to 15).

3/4 ounce of Hallertau at 45 minutes works nicely. Liberty, Tettnanger, Mt. Hood, Vangaurd, and Tradition will substitute OK. Just watch the AA's to calculate the IBU's