sorry I should have clarified - my current barrel collection includes a 1x 0.688 UL back in dust black (aluminium) and a 1x 0.688 Titanium UL back amongst others. I preferentially use the Ti back so I guess the 0.688 standard UL can go to a new home.
The 0.692 is just a backup in case the 0.688 can't cope with certain types of paint (which is why I am still keeping it).
I do not have a red UL front unfortunately.
Probably will be listing the 0.688 UL back and DYE boombox case for £14 each (inc. P&P) or £26 if bought together.