Try Gustharts, I have the same chainsaw as you and have had my old chain sharpened which cost £6 and purchased a new chain for £17. The new chain model no is OM91VG 60E 18"/45CM
Gustharts are on Tel 01670 789701
Les, from Lichfield, March 2009
Try this site M8 - have used before and are pretty good - https://www.gustharts.com/compatibility/search/model/?category=2&maker=gardenline