Not particularly rare or wonderful, but if in a good shutter a very usable normal lens for 4x5. Ole Tjugen (send him a PM) might be able to suggest a replacement shutter that will accept the cells and give the right spacing.

If you can't get a proper replacement shutter the cost-effective way to get a normal lens for your Wista is to buy a modern lens from KEH. The last time I looked they had heaps of 'em priced below the cost of an improper shutter in good order (all used shutters need a CLA, its a law of nature) plus adapters to accept y'r Dagor's cells.