Casacade or Willamette In American Wheat

I am brewing an American Wheat Beer today from a recipe off northernbrewers site. The recipe is as follows

4.51 lb American 2-row
4.19 lb Midwest Wheat Malt
0.52 lb Crystal Malt 10°L
0.5 Summit (5.0%) - added during boil, boiled 45 min
1.05 oz Cascade (5.5%) - added during boil, boiled 10.0 min
1.05 oz Willamette (5.0%) - added during boil, boiled 10.0 min
1.05 ea Fermentis US-05 Safale US-05

I can't get Summit hops, so what would be a better substitute ounce of Cascades or Willamettes for the 45 min hop addition? It is supposed to be an overly hoppy American Wheat keep in mind.

Oh yes sir, excellent combo! I am brewing my standard this weekend actually. It uses 1.25oz of williamette at 60min, then an 1oz of Cascade at 10min then an ounce each at flame out. It is yummy! 5lbs 2-row, 5 lbs red wheat. It is only like 25 or so IBUS but you can taste it with that clean malt profile and the clean WY1010 yeast- US-05 should give you the similar results. When I pitch a good starter it will be done in a week and ready to drink in 3 total. Sometimes simple is best.

I'm brewing a wheat beer this weekend and I was going to go all willamette... but I like the OP's idea of combining cascade and willamette. I think I'll do the same!

Whatever gets you the bitterness you need.