What is the intended purpose for this gun. This will help for suggestions. Under $100 is typically a pretty tough price range for power. Crosman Vantage with scope would be a pretty good starter for $100. It does shoot a bit fast, however. The problem with "high power" is that the pellets typically become unstable in their flight and thus less accurate. It is a marketing strategy at this point to advertise FPS rather than accuracy, as this is what the consumers look for.

Alternatively, Flying Dragon Airguns have had pretty good reviews from what I've seen and being manufactured in China makes them quite a bit cheaper. The Xisico XS46U at $135 uses an underlever cocking mechanism to keep the barrel straight with the intention of making the gun more accurate. And there is also a break-barrel Xisico BAM XS25 for $125 would be good options for cheap, accurate, quality rifles.