From experience I can vouch for the Meopta Opemus series of enlargers. These usually come with glass carriers and have masking strips in the neg holder. Ideally you'd want 2 lenses, an 80mm and 50mm, you can get away with an 80mm for smaller enlargements from 35mm if you can only stretch to the one lens.
I also have a LPL C6700 which will do 35mm to 6X7, this is less agriculteral than the opemus and smoother in use, but cost me twice as much.

One caveat with the Opemus is that some earlier models had a smaller that usual thread, and new lens mounts for these aren't easy to come by, spares for the later models, however, are available, at least in the UK.