You have to go to any nearest bank to you
And make the payment ok 120usd to the shipper address given to you
From your pocket first
Via money gram
Payment of 150usd
Once you finish making the payment a receipt will be issued to you
Scan the receipt and send it to paypal via the confirmation of payment message you receive from paypal
Once paypal sees the receipt paypal will verify it and release the 468usd to your account immediately