Well relatively cheap anyway. I just bought a boxed set of 18 ER32 collets, 3mm-20mm, made in Germany, for =A370 brand new from WNT in Sheffield. They aren't the super precision 6 micron runout collets but the 20 micron jobbers. Still far more precise than I'll probably ever need to cut to anyway. They've got a special offer on these running to 30th November if anyone else needs some, but you have to sign up for an 'account' before they will send out their tooling catalogue.
Peter