I can recommend two red dots:
1)Millet SP-1, one inch tube, comes w/rings, see thru scope caps, about $150.
2)Ultra Dot, one inch tube.
Both of thes models have seen numerous rounds through a .454 and guns of less recoil and are still going strong, they have variable red dot power (put on low during cloudy, dusk & dawn times or crank it up on sunny days), and small dots (3 MOA).
One thing to watch is the size of the dot, a 12 MOA dot will cover up at least 12" of your target at 100 yards! The smaller the dot the better.
Del