We do not currently offer the table tops for order separate from the bases on the Herman Miller Store. Since the segmented base for the 48" top and 42" top is the same, you are able to switch out the tops and keep the same base.
We would recommend contacting a Herman Miller authorized dealer or retailer in your area to order the replacement top. To find the location closest to you, please use the following link:
http://www.hermanmiller.com/where-t...You can also contact Inform Interiors (Phone: 206.622.1608) in Seattle for your replacement top.
If you have any questions, or if you would like our help with setting up the service for your table, please give us a call at 888.798.0202.