1. I found this tracking for you:
Number: LK035225640CN
Package Status: In Transit
Destination Country: United States
2016-10-11 23:21 CHINA, SHENZHEN EMS, Processed Through Facility, Your item has been processed through a facility in SHENZHEN EMS, CHINA at 11:21 pm on October 11, 2016.
2016-10-11 07:20 Origin Post is Preparing Shipment
2016-10-11 07:20 CHINA, Acceptance

Origin Country: China
2016-10-11 23:40 Shenzhen, away from Shenzhen to Los Angeles
2016-10-11 07:20 Shenzhen, Shenzhen Yu an Center Sales Department has been received (the embrace cast member name: Song Zhihai, Tel: 13809895351)
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2. And also this one:
International Mail# LK035225640CN Tracking Result
Summary
Tracking number Origin Destination Status
LK035225640CN CHINA UNITED STATES On route

History Detail
Local date/time Activity Location Remarks
11-Oct-2016 07:20 Received by Post Office 518133
11-Oct-2016 23:21 Departure export customs SHENZHEN EMS

3. So according to the above tracking we know that the parcel is On Routes to USA. Your seller is right that because there was a week long National holiday in China from the 01-08 Oct your parcel might be delay slightly.

4. Normally we can see some movement on the USPS site when 9 days have gone by from the last tracking in China. But because of the holiday it's will not happen. There is also some more people that are expecting parcel at Los Angeles and they are delay also.

5. I guess you need to hope for the best, be patient and track you parcel on the USPS site for any movement. I hope it come sooner then later for you.

Hope this help.

1. You have movement on the USPS site for your parcel.

Hope this help.