I might not be in the UK but I do got an E3 flasher and am in Europe.
What model PS3 do you have?

 

I'm willing to downgrade it if you can't find anyone else nearby (if you provide return shipping plus an amount of the work).

 

Well, I can't give a guarantee that it I can have it downgraded for 100% as there might always be something that might go wrong but with a bit of common sense and a bit of knowledge, I can at least assure a 99% guarantee I can have it downgraded.

The 1% that I can't is YLOD issues or previous NOR dump attempts that weakened the legs on the NOR chip sufficiently that they break when I attach the NOR clip.
This shouldn't happen if it's brand new or hardly used ;p

I've downgraded a dozen or so PS3's and never did it went wrong once.
Only failure I ever had when hacking any console was a Falcon that refused to boot on RGH2 and accidentally messing up me own old Xbox by flashing a 1.6 EEPROM to a 1.2 Xbox.

Oh and a few weeks ago, one of the legs of a 360 DVD drive snapped off when it was shipped to me.
I mended it with a dab of glue, wrapped it up nicely in the package it came in and arrived with a broken leg again.
I blame the incompetent fools at the post office for that.

If you're doubting, I can refer you to some people that will help assure you I won't scam you.
Other then giving me word on me 13k+ posts and years old reputation here on Temp ;p