Gerry,
Do you have guy wires on your tower? How long are they,
and how hard would it be to put an insulator on the top end
of one, or several? How about loading the tower? Or running
a wire from the top to some point close to the shack, or a
tree / pole / top of the garage? All kinds of possibilities.
An 80 or 160 meter antenna doesn't have to be of any
'classic'
design to work. You may have to use a tuner, but that's no big
deal. Guess it is if you don't have one, huh?
'Doc