That's awesome! And for sure! All those factors are involved in taking care of a prized replica!
But I still think it's a risk buying something so old that relies on electronics, even from someone who has taken great care like you have! If monies wasn't an issue I would take chance and buy one and feel it wouldn't be much of a risk, but unfortunately I am not made of money! 3 grand and up is a lot to take a risk on! : )
Sadly the electronics will fail on most collectibles of this sort eventually.