Please advise how many brushes you need.We will mail the samples to you soon.We can discuss the prices as soon as you receive the samples.
上面是逐句翻译的,比较简单实用,下面是合并了一个句子,其实贸易上的邮件还是简单点好：
Please adivse how many brushes you need.We can discuss the prices as soon as you receive the samples that we are going to mail soon.