Do you think it's okay if I try to sell a guy some more stuff?
Why do you want to sell him more stuff?
I need to make some money.
Unless he asked about other stuff it seems rude to contact him. I would be frustrated if someone tried to sell me something I wasn't interested in.
But I really need the money.
I understand that you need the money, but I don't think you should contact him if he hasn't shown any interest in buying more things from you. Maybe there are other people that you can sell it to. You might want to post a listing on an app or website.