That works, but it doesn't sound very natural/common. Your closing remarks also depend on how well you know the recipient of the message. Since I am guessing you don't know them well, my first suggestion would probably be best. Generally, these are accepted closers for a business email. I look forward to hearing from you soon (probably the best option) I hope to hear from you soon I am hoping to hear back from you soon I am looking forward to your reply

Yeah, that sounds perfectly fine. If you wish to be a bit less formal, "I hope to hear from you very soon," also works well. Don't use an ellipsis, though; just end the sentence with a period.

I want to send formal e-mails to sellers.

Looking forward to hearing from you sooneset.