A cooler is actually a really simple thing to install with loads of space for one, I did one some years ago, although I would prefer the original setup. Saying that, if I intended to keep the car for many years I might consider it.
One thing that's maybe worth a mention, I've emailed Rock in the past asking if they have a part that isn't listed and their reply was "if it isn't listed on our website we don't have it"