Bugeye (01 to 52 plate) or blobeye (03 plate onwards) sti would probably be the best starting platform. As the engines and gearboxes are much stronger and give more headroom for project creep .

If your sure that you'll keep it relatively standard and won't eventually want over 330hp the a low mileage blobeye wrx is probably the way forward imo .

If it's not broke .....upgrade it 😊

Exactly as above! 

Looking for something newer age wise. No an I 100% won't be doing power upgrades may do handling. 

How much would I expect to pay for one, best places to look an what's the expens on running one. 

There is no Subaru dealer now in Cardiff an have no idea where the next one is

Some examples for your sort of budget.  You would pay a lot more through a Subaru dealer typically. 

http://www.ebay.co.uk/itm/201601399255

 

http://www.ebay.co.uk/itm/311666400145

Yea it's more if I need parts or work I have no where to take it

Look for a Subaru specialist rather than a Subaru dealer. It's a minefield of course but you'll pay less labour.

Thanks I'll have a look online. Who or where do people in South Wales take theirs