I need to replace a fork that has a theaded steerer length of 146mm but the closest replacement I can find has a 200mm x 50mm threaded area steerer, the 175mm x 50mm version seems to be discontinued. Can a bike shop extend the threaded area so that the steerer can be cut to 146 and still have adequate threads for the headset? My alternative is to go with an unthreaded steerer and replace the headset and stem but that would add a lot to the cost of the project.

Thanks