The Dell part number is TH991 which leads to a Fujitsu MHV2080 BH, a 60GB HDD, the laptop is a Dell Inspiron 1501.
Dell advised not stocking anymore and to not fit anything much bigger than 150GB. Can get the identical replacement from UK and USA but I am up against a time constraint as it is going back to England with someone, rather than $130.00 postage.
Here in Oz they seem to start around 250GB and then up.
Point taken re the age, given more time I would have fitted a new HDD.