I only know that ESE was a music shop in Maidstone who produced their own range of music gear. Mainly PA but a few other amps and cabs as well. I never tried any ESE equipment so can't comment on sound or quality. Sorry.
If you want to protect your name, this is the route to go down.
https://nationalbusinessregister.co.uk/services/business-name-registration/
and also,
https://companieshouse.blog.gov.uk/2019/02/12/choosing-a-company-name-trading-name-or-trade-mark/
Personally, I would just sand it. You've had it for a few years now so I would assume that you've got no plans to sell it, so sand away. If you ever want to sell it then you can fork out for a refinish.
I can only agree, certainly the best and the inbuilt modem actually works!
Since my then band folded during covid, I've had one sitting around doing nothing. I think I might just sell it. It will be a lot cheaper than the prices you've seen.