There is a dealer in Barnsley/Rotherham way gets some clean examples in I got mine there 5 years ago an 05 WRX was completely standard Unmodified example with full service history and I’ve had no issues with mine and know many others with 2.0l boxer engines still going strong
As has been said, they are not unreliable cars if well looked after. Had my 2005 STI 3 years and in that time all it’s needed other than servicing and consumables are rear KYB shocks to replace the sticking originals. It’s my 4th Scooby and never had any reliability issues at all.