Wouldn't a dry sump tank work here?
Get a good one and you should be able to get it with heaters built into it.
Basically then it works like a home hot water heater...large volume of liquid (
oil in your case) is stored in a tank with heating elements built in to keep it at a desired temperature.
You don't necessarily need a dry sump system to make use of the remote tank, but that might be nice too.
The tank would definitely require more room under the hood than just the loop through the bottom of the radiator takes.