you get what you pay for!
As a farmer, you need several types of cover, you need Employers Liability and Public Liability to start with. You may then have buildings that you might want to insure. these migth be for just fire, or storm as well. You might have livestock. You migth want to insure the livestock for accidental death, death in transport, death whilst calving, diseases etc. You migth have a tractor which must be insured if going on the road. Even if it is not on the road, you are well served to have Third Party on it. You migth want fire and theft or comprehensive on the tractor. You might have other vehicular equipment, quads, mowers, balers combines etc and again you have a choice of covers.
If you are looking simply for Public liability and buildings insurance, I would reckon you would have change out of €750, which is not bad. What are you being quoted by FBD and Hibernian?