No, just GZ33 and GZ34/5AR4. I prefer the GZ33.
If you look at the ratings, the GZ37 should not be used with a first PS cap greater than ~4uF due to too great of a current draw on the tube; the first PS cap in my Chenin is 3uF. Yours is probably close to that. Maybe that's why the GZ37 died?
The GZ33 can handle a lot more (up to ~60uF, I think I read somewhere).
If you look at the ratings, the GZ37 should not be used with a first PS cap greater than ~4uF due to too great of a current draw on the tube; the first PS cap in my Chenin is 3uF. Yours is probably close to that. Maybe that's why the GZ37 died?
The GZ33 can handle a lot more (up to ~60uF, I think I read somewhere).