You can purchase an unstoppable domain at http://unstoppabledomains.com/
If you don't want to watch the video above the steps are:
Import your zilliqa_wallet.json into ZilPay
Deposit ZIL into that new wallet or transfer your domain using unstoppabledomains into your existing ZilPay wallet
Click on "Sell" at the top of the page.
Select the "NFT is already in my wallet".
Select "Unstoppable Domains".
After you have entered your domain name, click "Check Domain"
If you own the domain and its in your wallet, you will see a green checkmark.
You can see "How to list an item for sale" to learn more about this step.
You have two transactions to submit.
Approving the domain name to be sold on Mintable.
Listing the domain name for sale.