Good plan!
The only "traditional" 6.5mm bullet in the 155-160 grain range that I'd consider right now (because I have experience with it on game) is the 156 Norma Oryx. It works very consistently--though not any more than the 140 Partition.
If you read enough of the older writings about the magical 155-160 grain bullets in the various 6.5's, you'll find some instances where they didn't work so well. And that's been my experience with the 160 Hornady RN from the 6.5x64 Mannlicher-Schoenauer. I've seen it break both shoulders on an average Montana whitetail doe and exit--and seen it not reach the far side of the ribcage on a behind-the-shoulder shot.
