You didn't say which speakers you have, But if they are 4 ohms I have some suggestions. A MC 7200 will put out 256 watts continuous and 324 peak, 8 ohms. At four ohms 392 watts continuous and 544 watts peak. Another choice would be a MC 352, which puts out over 430 watts continuous and is a quad balanced amplifier. As much as I like the 7200, the 352 is from a totally design and performance plateau, and is what I would be looking for.
But remember the 352 is only a 4+ db increase, and that usually isn't enough for most folks. We always recommended a minimum of 5 to 6 db increase if power is the only criteria. The issue for you is quality. And a 352 isn't going to match a 152, it will be similar though. And 301's aren't the answer either. You know where this leading don't you. two 601's but thats out of the question. Go listen to a 352.