I am looking to replace a sylvania 12sq7GT that I dropped (!*#%$!) on
the floor when cleaning my Hallicrafters Continental Shortwave Radio.

The diagram on the bottom of the radio shows the tube that should be in
there to be a 12SQ7 with no mention of GT (that means glass tube right?)

The tube I broke was working without flaw and I would like to replace
but I see there are the metal enclosed military type tubes as well.

Without getting too technical can anybody let me know which types or
brands are best for a am/shortwave radio?

Please post advice.

Regards,
malomarski