I paid much more than that for my '51. However, I'm in Florida, where nothing survives for that long anyway, and there are few, if any, Big Bolts available down here.
I think it depends on how badly you want a project of this magnitude. I'd been wanting a COE for a long time, so it didn't take much convincing myself that this would be the one. As for being practical?

Don't even go there! You'll be spending a lot of time & money, for sure. But I've had a ball working on mine, and everyone who sees it thinks it's cool, so there's the 'pride factor' to consider! I consider this a pretty exclusive club, even if we are all nutballs!
~Bruce