Visa stamping when new H1B is in process

[vanv]

Hello-

I am in H1B extension - valid till  Jan 2018. I changed my last name in passport because of marriage related. My company decided to file a new H1B as they thought change in name is a material change. So, new H1B is in process now. Same employer, same job just the change in last name. Meanwhile, I lost my old passport (that was in old name) that had the h1b visa stamping (expired).  I have the police complaint.

My question is -

Is it advisable to travel to India and go to visa stamping with new passport (new name) and I797(old name)? I also have the receipt of new H1B application in new name and just the copy of old passport/h1b stamping. Would it be safe to wait till I get the new H1B processed before traveling?