Warco and other makes of mill-drill are perfectly good and readily available. Round column mills get some bad press from the usual brigade for whom only a gold plated Bridgeport is good enough but they are perfectly adequate if you have the brains to use them sensibly.
Sieg do a range of sizes but the column fixing on the small ones is rather a let down.
A Centec or Tom Senior are probably bigger than you are thinking about now.
Another small one is the Hobbymat BFE but not very common.
BTW a miller is the person who operates a mill or milling machine.