Hi Mate
do you have any more info on it.. anything that someone will recognise?
Also have you checked with DVLA it is still on the road? https://www.taxdisc.direct.gov.uk/EvlPortalApp/app/enquiry?execution=e1s2
welcome to the subaru Owners Club
Check for oil leaks, check for camshaft seals, front seals etc. make sure its had all the servicing as possible. Cleaner the history the better