Bubblesburst; try World of Water in Timperley, they keep them in cubes so don't be shocked but they get some stunning Betta in.
Last time i was there (i don't know Betta terminology, so don't laugh) they had a;
Almost pure white betta, showing a little peach. Think it may have been a veiltail.
A black crown tail.
A couple of wild caught Betta, don't know the species, one was labelled as a Mountain Betta

A few plakats, if these are the wild type betta splendens.... with the narrow tail...
erm...
Give them a go, ring first but they do get some lovely Betta.