Hiya Limpabit,
Don't know if this site will help you, looks like you have to do a VIC (vehicle identity check) by the DVLA and they tell you if it needs an ESVA. Almost certainly, as they are only another one of Gordons Agencies of Extraction.
BTW. The SVA inspectors are only private companies (subbies) working for the government, as are MOT stations. They are not VOSA or DVLA.
http://www.direct.gov.uk/en/Motoring...cle/DG_4022316
Best o' luck out there
DeeJayHarry