[Heathkit] replacements/substitutions for 8873 tube?

[Ian]

For somebody NOT on this reflector.

***PLEASE DO NOT REPLY TO ME!!!***

Reply to him: 
ehertz at tcaf.org

 
 
hello all,
 
been considering getting a heathkit SB-230 linear amp, but I understand 
the tube it uses is difficult to find. I was wondering if anyone knows 
of a replacement or substitution that might be more available? Or 
whether anyone has designed a modification to the amp that could allow 
it to use a different tube?
 
thanks
Eugene