[Heathkit] 6C10 tube hard to find!!!

[Dan Pividal]

Anyone knows what to do when 6C10 tubes are no longer available?
The tubes are getting very hard to locate and very expensive.
They are selling at $18.00 to $25.00 dollars. The guitar amplifier guys are 
killing us.

They are used in the Heathkit SB-610 scope for the horizontal amplifier and 
the sweep generator.
What can be done when the well runs dry.
Any tubster replacement anyone know of?
Dan/N4VET