I recently had to rely on my old, and normally unused, Frontman 15G (

All good until yesterday, when I started to hear what seems to be a voice coil rub sound (not sure how I can upload an audio file, but I have a recording to share in case). Anyway, the speaker is surely not working properly and the amp is almost unusable with clean sounds. I guess this has to do with the fact that I frequently use an octave shifter pedal set to 1 octave down in combination with a Proco RAT 2 to get some kind of Royal Blood or Muse like sound. Even if I never went above volume 3, I guess the speaker was so cheap that it could not handle this properly and got damaged.
So I was thinking of replacing the speaker with a Celestion Eight 15 (https://celestion.com/product/8/eight_15/), to fix and also improve the amplifier.
Do you think this speaker would be able to work fine with an octave shifter+distortion (again at low volumes, less than 3) or will it also likely be damaged?
Alternatively, do you know any good guitar combo that costs less than 150 USD or EUR that could do the job? And what specifications would be the crucial ones? Speaker size or frequencies maybe?
Thank you, hopefully this is also useful to other users!