Hey, since you're developing the frontend part using the TypeScript SDK, you can make use of the getOwnedObjects method. This method allows you to retrieve objects owned by a specific account and filter them based on the struct type you are looking for. You can do this by passing the StructType filter argument in your request, like so:

suiClient.getOwnedObjects({
  owner: "0xCAFE",
  filter: {
    StructType: "0xCAFE::module::struct"
  }
})

This should help you get the custom Sui token object ID you need for the specified account.