WELCOME ABOARD!
I don't know if it can be fixed, but if it can someone will be along soon with the answer.
How was yours destroyed? Shell hit? That would do it. Depth charge? If so, was it down or were you looking through it? The tubes were fairly rugged, but the optics were quite delicate. If a connection was fractured the tube could fill with water and leave it useless. The prisms could be knocked out of whack without much trouble.
Not trying to discourage you, and everybody has a right to play the way they want. Just pointing out some of the real-world problems with the things.