Yes it is called the Antiguo Europa, situated on the corner of Emiliano Tejera and la Meri?o, just down the little hill from the ruins of the monastery. I checked it out recently for a friend who is now staying there and paying 65 dollars for a single room. The singles are nice, not huge, as you will find in some of the Colonial hotels like Nader,but perfectly adequate. Restaurant on roof, with nice view of the zone. Right around the corner from the Atarazana, and just up the street from the Parque Colon. It was not a hotel previously.
Appears to be pretty well managed, certainly clean and orderly. Windows facing out on the Meri?o might get a little noisy in the a.m. with the traffic descending on the colonial city, but it could be that the windows seal out the noise.
There is another new place as well, just a block away on Vicente Celestino Duarte no. 19, called Hotel Atarazana, but I have not yet had a chance to check it out. 65 bucks a nite.