It's very very hard to do commercial free range pork in this country. Almost all commercial producers need to finish indoors - and that includes organic ones.
The supermarkets tried to be honest, labelling their pork and sausages, "outdoor bred", but were villified for that. In truth, "outdoor bred" is the best you are going to do on any widely-available product.
If you really want free range (and there are debates that could rage and rage about whether raising weaners and finishing pigs outdoors
is better welfare in our wet climate) then you need to be looking for the niche products like Helen Browning's - though I'm not sure that even she can finish outdoors; she may have to bring them in for the last month or so, at least when it's wet - or going to your local smallholder / farmers' market - or, of course, TAS!