I can tell you this from experience.
As long as the voice coil is in good shape... you can use Duct-Tape.
Duct-Tape ...I know I know .... Hey! it got me through many a show until I could save the money up to have the speaker rebuilt.
But it looks like your not pushing near the Watts we did.
But it's worth a try if moneys tight.
I did try air filter foam one time and that worked quit well but it's no where near as tough as Duct-Tape.
Wow.
That brought back a few memories.
