>>1807596You have to include 36t in your search to find them from online retailers. Here's a quick screencap that shows the relevant lines.
Climbing gear on different bikes really varies, but the lowest geared drivetrain that would still be commonplace would 50-34 chainrings and an 11-32 cassette. And yeah, 20% is really steep, you have to be a strong climber to get up that at all - even with low, low gears some riders would have to walk that since at some point your riding speed drops below walking speed or what you practically need to stay upright.
