North p.168 shows you the regional variations in style, so in answer to your question, yes, there is no standard form. According to him they were made in 19 regional centres, so whether at the local mint in this case is another matter, and I don't know the answer. For further reading consult Anglo-Saxon Monetary History by Blackburn and Lyon, pp.223-72. I don't have it.
The style looks ok for the area. Winchester is the closest shown - which makes sense.