This is only a maybe, but consider whether or not the following is possible:
If your original transport over for your own use included a box suitable for shipping, have your agent put the items in such box. Meanwhile, go on UPS or similar and use a credit card to pay to obtain a shipping label from yourself at his address to yourself at your address. Fax it to your agent to be affixed to the box. Have your agent take the boxed items, which he has hopefully never touched to the appropriate depot.
You need to be the person who puts the shippable items in your agent's hands.
As if you had shipped guns to a shooting venue and then set them up to be returned to you, for example.
Otherwise, you have to go be your own agent and hop in the car.
No one with FFL responsibilities or sensibilities ought to do this for you with the current state of the law and enforcement.
