Well, if easy overclocking (just changing the multiplier) is worth $20 to you then yeah, you could do that. But you can overclock the other stuff normally. But there should be multiple Athlon II x3 models with prices ranging from $70-90, not sure how you're figuring only $20 (assuming $120 for the phenom version) difference. Your link says the CPU is unavailable, so if that's where you wanted to get it, well, you can't.
And between the athlon II models there's only a few hundred megahertz difference which wouldn't really be noticed and especially not if you OC it anyway.