You sound fast so you can probably run a 100 meters in about 11.0 flat.
Thats equivalent to 4.9 for the 40 and slow NFL linemen run that so I'm sure you are at least as fast as them.
So lets say 11.0 for the 100 meters is good for you, maybe a little conservative. Always good to be on the safe side.
But you aren't a sprinter so you can probably carry that pace for a good ways given you are a distance runner. Probably 500 meters or so.
That would be 55.0 for the 500.
But then you haven't really gotten into serious training yet, and so once you do I'm sure your endurance and probably speed will really improve, so you can probably get to the point that you can hold that pace the whole way.
So that would put your goal time at about 1:50. Yup that sounds right.
Go for it kid!