try a nuffield or leyland cheaper to buy and nothing between them on the belt. there was a cheapie on flea bay but its gone.. theres a few majors on there
http://www.ebay.co.uk/itm/LQQK-FORDS...item4ab405b12a
there was a tidy nuffield universal cambridge way for around a grand with a belt pulley ex farm.....but can't find it probably sold! theres a few about on there... you killed your old one?