Portable DAT recorders were made by Sony, Casio, Tascam, JVC, Aiwa etc.... I think I had at least 3 different ones. All of them were finicky, and one I had - had a 'backdoor' switching to defeat the proprietary SCMS coding. Unless you really have a reason to own a portable, a desk or rack version is much more stable. These had a short market lifespan, and I believe you'd have to scour the second hand market for one now. A MD recorder pretty much does what a DAT does, and if you really want to get a fully professional portable recorder, get a Nagra.
C'est un Nagra. C'est suisse, et tres, tres precis