Here's a 505 restoration article that you may find interesting:
http://antiqueradio.org/halli505.htm
I believe you can order 6KV caps from
http://www.justradios.com/ as well as Allied.
I was thinking I had restored mine not too long ago, but the article has a screen shot from the 2002 Academy Awards show -- time flies!
Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html