Anyone know for a place I can get a 300 head pressure tested in the bodmin/liskeard are of cornwall that wont rob me?

I already got it skimmed by Adrian at doublebois thanks to the guys on here,but I have had so much trouble with a replacement head that turned out to be faulty (that has been on and off several times) that I want to be sure that this one,a genuine LR part,is good before it is fitted.