I would like to purchase a specific power tool (Groove cutter) not available in my country but would like to import it from a country were the power source is different (220V 60Hz) and to then change the power plug to suit my own country (230V 50Hz).

Going by a bit of Googling I have found that it may not be a problem but seeing as the tool is quite expensive I would like to ask and be sure that it would safely be able to handle the small change in power and difference in frequency.

Thanks

Why not ask the manufacturer of the tool? You could then check on the
warranty should damage occur...