I found this place PMT. So this guy Trevor, older English guy, very nice, talks to me, looks at the guitar and makes some measurements, checks it out etc. Very cool guy, btw! So normally this costs 90 pounds all together. He however tells me it is ok and a fret levelling wouldn't really help (it is in fact theheavy gauge of strings I use and - mostly - that I downtuned the guitar to D standard). He then widened the nut slots for me that was on my list as well, which took like 5 minutes. I ask him what it costs and he tells me "ah, nothing, that's for free"!!!!!! Awesome! I already love that store. I almost felt a bit bad for not paying anything.