回複：what can I do now(urgent)

If you really want the job, you can talk to the hiring manager directly and frankly. you might think to seek a higher salary from the manager. I would talk to the manager the following.
I really like the job. however I need to apply for H1. The offered salary is less than required for applying for H1 visa. The required salary is $.... I wonder whether you might raise my salary.
By my feeling, if the manager really wants you to work for him and the difference of the offered salary and the required salary is not too huge, he might raise the offered salary.
if he does not agree to raise the salary, ask him if you can change to part time. if he still says no, you might look for another job.
Good luck!