Hi Gaz
You should be looking for a d og with the names - Rillington, Gutchcommon , Eakring , or poss Minkstone (though my knowledge on the latter is limited).
Alternatively a hybred Bed /Lakie is usually a safer bet and usually with a better coat.
I paid £200 for my pup, he's from working parents and good bloodlines so if he doesnt make the grade I'll have to blame myself.
As for the agression - I've always found them to be ok with dogs they know but obviously terriers are terriers and you would expect a certain amount of agression with any game dog.
SwanseaJack seems to be up to date o