How hard is this climb and how long should i be taking?
A common measure of fitness in the pro peloton is watts per kilogram, or how many watts of power can you generate per kilogram of body weight for a 1 hour effort. This is more or less a direct translation into your climbing prowess.

The "magic number" for pro racers is 6 watts per kilogram. I would say that for a recreational rider anything over 2 watts per kilogram is pretty good. 

You can get some estimate of the power required for a climb via various online calculators. They are at best a good guess, but for climbs without headwinds at speed less than 20 kph, reasonably accurate.

These numbers will not be super accurate, but will give you some idea of what is typical.