Treasure it and use it! I can gurantee you one thing: If you don't use it, someone else will use it in the distant future, and they might not appreciate the razor as much as you.
I was lucky enough to find 2 NOS Eveready 150s on eBay for about $15 delivered and have been using one of them as my only shave brush for about 3 months now, works great! It shed a little for a week or so and has been stable ever since, I'm going to see how long it lasts.