Here is a link to a cryptothrift listing
https://cryptothrift.com/auctions/physical-crypto-coins/graded-cryptolator-physical-bitcoin-silver-1btc-2/. They can act as an escrow or I am fine with the usual escrows on bitcointalk.
Description: "This is a Cryptolator 1oz silver \’unchained\’ series physical Bitcoin in the denomination of 1BTC (unfunded). You will need to add your own bitcoin to the coin. It has been graded by ICG and received a MS-68 rating. This is an excellent rating for a physical bitcoin. ICG is one of only two of the top tier professional coin grading services that accept physical Bitcoins for grading. This coin comes with a certificate from the manufacturer. It has a multi-signature private key under the hologram that adds an additional layer of security. You will receive a card with one of the two signatures required to unlock the private key. The second signature required to unlock the private key was secured under the hologram on the coin itself by the manufacturer. So, not even the manufacturer has had access to the full private key. Additionally, the coin is secured in an air tight slab from ICG.
I had several of these graded if you are interested in more than one. You can verify the integrety of each coin and of the multisignature with the Crytolator dashboard on the manufacturer’s website. Let me know if you have any questions."
Asking price is $189.98 with free shipping within USA or $15 for international. Paypal is fine with a confirmed address, but I do ask that you cover the paypal fees (3%).