Your post is also in the USA so the Dollars to Euros might be different, the cheapest P67 MOBO that I recommend is the ASUS P8P67-M PRO.
You MUST verify that any P67 MOBO you consider will allow for OC of your 'K' CPU; oddly many cheaper P67 MOBOs will not allow OC'ing according to user and confirmed reports. Further, you absolutely cannot use ANY H67 MOBOs; none will OC.
I'm going to be using the ASRock P67 Pro3 in my new build, which I should be getting within 10 days or so. It's fully overclockable with all the right voltage settings but doesn't have all the extra bells and whistles and slots, which is crap I don't need anyway.
The Pro3 is $140, which is a $20 savings I can use for bigger-better things elsewhere in the system.