There are several bikes in that price range. Make a list, and ride as many of them as you can. There are also many threads on this forum that discuss the merits of various bikes. Do a search on the bikes you might be interested in.
A short list: Long Haul Trucker, Trek 520, Cannondale T2, Windsor Tourist, Bianchi Volpe, REI Ranonee, Soma Saga if you want to build it up, .................................

Depending where you are going in Europe, get something with low gearing right from the start. With 50 lbs of gear I would just see "how low I could go".

My wife and I did a 3 month European tour last summer, including Switzerland, and the Pyrenees. Contrary to a lot of opinions on this forum, I was very happy with my low gearing. FWIW, I have a LHT (built from the frame up) and my wife was riding a custom built Co-Motion.