Yes this is a scam. The WHOIS information for the company shows that the site has only been running since June 17, 2016. The grammar on the site itself is poor. This site was hastily thrown together to look convincing but to deceive customers.
Insurance gets paid for before a package gets shipped and not once it's in the mail. Additionally, there's no such thing as refundable insurance. Finally, you'd never pay more insurance than the goods are worth in the first place. All of this is the sign of a scam.
Send no money. Report the fraud to your police, to the FBI at IC3.gov and to the Federal Trade Commission at FTC.gov. I don't know how you paid for your so-called goods but the online shop you used is in on this scam. if you used a credit card, take every precaution against identity theft as that card is likely compromised.
Just checking in to see if you need more help or any clarification of my answer. If so, please reply here on this question thread.