The recommended minimum time is an hour a day. My chinchilla lives right next to my computer desk and he gets taken out of his cage 4-8 a day for shorter spans. He is very well adjusted.
For your chinchilla what is going to be the most effective for bonding is to take him out in short intervals. You may need to start with a few seconds at a time because chins must be accustomed to being handled before you can tame them. Do this several times a day and then you can do it longer after a few days. If he starts acting stressed and shies away from you you'll have to back off. Make sure to have plenty of interaction in the cage as well where he does not feel threatened.
If he isn't bonded now, since it's been two months since you've had him, and he is an older chinchilla, it's going to be a long process that will likely take months. Another thing you can do is lock yourself up in a bathtub or shower stall for a few minutes and let him climb around on you.
As far as loneliness goes my pet likes interaction but not all the time. Some days I don't handle him much at all and that does not bother him. It will depend on the animal how much attention they will require to keep them happy.
