[bandersen]

Originally Posted by Steve McVoy

I also have found that ceramics work fine in the horizontal and HV.

Here is a $3 cap that will probably work in the vertical:

http://www.alliedelec.com/search/pro...x?SKU=70189472

That's only rated for 3,000 volts and 10x the capacitance needed.
Instead grab these while you can! 0.0047 rated for 10,000 volts and on sale for only $2 !
VT71s originally used 0.005 in the vertical and these are plenty close enough.

http://www.alliedelec.com/search/pro...x?SKU=70006900

While you're at it, they also have Vishay 0.001 ceramic @ 6 kV for $0.77 http://www.alliedelec.com/search/pro...x?SKU=70079541