Coffee deteriorates rapidly after it is roasted - after about ten days it could not honestly be sold as a premium product. Green coffee will last several months to a year before spoiling, but bear in mind that coffee roasting is a skilled profession for which you will almost certainly need to head-hunt an employee.
There are at least four specialty roasters in Ireland: Green Bean, Ariosa, Java Republic and Bewleys, and two commodity ones: La Scala (Bewleys again, but high volume and low quality) and Robert Roberts. You should note that the standard business model is that the supplier of beans to a restaurant also supplies and maintains equipment for free or a nominal rental; training of staff will also be required, again for free. Coffee brewing equipment is expensive - a pretty basic two group commercial espresso machine and grinder will cost at least €2,500 and high-end equipment will cost much more. Used commercial equipment is available for fractions of that price, and if you can find a competent maintenance engineer to work for you rather than contracting a company to do it you may find that repairing used equipment can save a lot of money.