Hudson and Allen ones are still available that Robert mentioned. I just added some to my Panther build. I picked them up at a LHS but have seen them on the net. Of coarse I did'nt save the site but I found it on google. I like them allthough wound up using the plastic kit ends instead of white metal since I could not get a drill bit small enough.
Here's a couple of places that have them
http://www.michtoy.com/MTSCnewSite/scenic_diorama_folder/Hudson_Allen_folder/Hudson_Allen_scenics.html
http://www.rjproducts.com/Catalogs/Hudson_and_Allen_Studio/Hudson_and_Allen_Studio.html