I am not sure that ordering the floorplates is worth the shipping cost, but factory retail non-LE is $11.95.
I have purchased several magazines at very good prices from http://www.calssportingarmory.com.
They carry all of the HK line and can order
any parts in that you need including the baseplates.
You may also want to try http://www.ccfa.com additional places to post your questions may be found at http://www.parkcitiestactical.com (click on the BB link) and http://www.hkpro.com (scroll down to the bottom of the page and enter the BB or go directly to his sales page. Park Cities has a great P-7 discussion area while HKPRO pretty much covers anything HK.
Go to http://www.calssportingarmory.com . He is located here in Denver. He stocks extended floorplates for all models. They run $5.95 last time I bought from Chad(two or three weeks ago - 6 USP 45 full size extended floorplates for my tacticals). If he doesn't have them in stock, wait a few days (or weeks) and then try again. His biggest problem seems to be that getting parts from HK is a hit or miss proposition. But, Cal is THE MAN when it comes to HK parts. And his prices are some of THE LOWEST anywhere. Hope that helps.
<font size=-1>[ This Message was edited by: Wallew on 2001-05-03 19:42 ]</font>