There are other simple to implement ways to shorten lead times. You can identify critical path items with long lead times and consider purchasing an amount in advance to keep in inventory. While this will increase your inventory costs some, it has the potential to shorten lead times significantly.
You can also choose to build to stock inventories of sub-assemblies that can be configured into a number of final products. Again, for a small increase in inventory costs you can shorten lead times of product without having to commit raw materials to specific final products.
In many cases sending your forecasts electronically to your suppliers can shorten the overall lead times. This technique requires a close relationship with your supplier and will entail linking your back end systems.