This film is available on both Blu-ray (1080i) and DVD in Region A/1. The extras are similarly lacking but the Blu-ray apparently has a Booklet with an essay and an interview with the director and the DVD has the deleted scenes and an Interview with Director Yorgos Lanthimos (12:57) and a photo gallery. Apparently, (there are only a couple of reviews on-line) the DVD features the artefacts problem. Up to you.
A reader, Sean, kindly provided more detailed release information as below: The film has been released (on 20 September 2010) on R2 PAL DVD and 1080i/50Hz Region B Blu-ray in the United Kingdom by Verve Pictures, and these releases only contain the UK trailer. I have personally seen the UK region B Blu-ray and can confirm it has some print dirt, likely the "blotches" you make mention of for the R4 DVD.