Mirko There are some good deals on the U.K. e-bay with a problem. 1. Enlargers being the size they are most sellers want you to pick them up rather than go to the time and trouble of packing them. They can be dismantled and packed but expect a hefty postage bill.
2 ways round this. 1.Is there a separate e-bay for the Republic? 2. Find a N Ireland seller which makes a pick up feasible. It's crossing the Irish Sea that's the difficulty but there may be little choice. It's the biggest single item you'll ever need and a trip in a car/van to the U.K. might be worth it as it's only once
A couple of U.K. retailers sell secondhand enlargers and might ship to the Republic. Try calling Secondhand Darkroom Supplies or Nova Darkroom. A google will find both phone numbers
Finally there are a couple of active subscribers here from the Republic whom might come up with ideas.
I suppose that the now closed darkroom has sold its equipment but if the owners are contactable they may know of sources of enlargers. Always assuming that you haven't thought of that.
Best of luck