I bought a 4/3 ION Quantum on line last week from DexterSurf - wore it on Monday in a balmy 11 degree day with apparent temp of 6 degrees - super toasty warm - flexi forearms (no arm pump despite pretty radical conditions and lots of boom holding in the mega gusts)
Price was really good - not sure how many they have - free post as well.
Worth emailing them to see if they have any more if you want a bargain (I'm not a fan of front zipper wet suits)