As bose said, I've never had a problem getting a MATZ pen from them. Your proposed route looks good and you'll find the river a great feature which will take you straight onto right base (the most likely join they'll give you if they're on 26).
Not sure on the handling situation as I have only come in to Bournemouth "as a visitor" once, but I managed to avoid most of the expensive handling etc as I was visiting one of the based companies there and paid my landing fee through them. Might be worth a try if that's what you're doing (or you know someone who works there
)