There is a bridge of this design - highway variety - at the St Mary's River in Duluth. The highway department condemned it and planned to replace it (near 100 years old) - but the local community objected. Quite a landmark in that area. An engineer of my aquintance was assigned the job of restoring it and modernizing / certifying the structures and mechanism - it took several years. The cast top sheaves had cracking at the hubs - old wounds - structures were riveted and rusted - many problem areas. Some not so easy to duplicate with modern safety standards. He did a great job and the "new" bridge is not easily distinguished from the century old bridge and way more reliable with new sheaves, gearboxes and electrics.
