http://www.redmusicworks.com/index.html
https://reverb.com/marketplace?query=red+music+works+natural+booster+nb+5&_aid=kingman
As far as clean boosts go the Natural Booster NB-5 from Red Music Works is one of the best I've ever tried or heard. It adds perceptibly nothing to the guitar's tone but extra decibels. This is why I demoed it with the DRW guitar - so you can hear for yourself. It is clean, clean, clean.
At the time of writing the Red Music Works website does not have an English page so I can only guess how much extra boost the NB-5 will give you. That guess is around 10-20dB.
Guitar: 2016 DRW Custom Guitars BK63 with Blu-rock BK63 Pickups. (see: https://www.facebook.com/blurockcustompickups/?fref=ts)
Amp: Laney VH-100R & LT212 Cabinet (Greenbacks).
Extra effects: Eventide H9
Cables: Providence
Power Supply: Voodoo Lab MONDO
Mic: Violet Design "The Amethyst Standard" (amp) Samson Airline77 (me)
Camera: Canon 60D (me) and Sony HDR CX190 (pedal)
Soundcard: AVID Mbox Pro 3
Computer: Apple iMac 27" i7 3.4 GHz 16 GB RAM
Software: Pro Tools 12.4, Waves CLA Guitars (slight comp over input track), Waves L3-16 Limiter (to keep levels in check at output), Apple Final Cut Pro X (video editing and Youtube compression).