Retrieved two pics off the web page: model is from Japan (ref pic).
99% sure it was made by Sanyo, early to mid-1970s, most probably.
Rebadged and sold in North America, just like an Kenmore twinnie
equally made in Japan by Sanyo at about the same era as this one.
Did use one of those years ago. Interesting models. Efficient and
solidly built--except for some plastic parts which tended to dry
out and crack over time.
it seems more to be Sanyo (or, possibly, Toshiba) rather than Hitachi...
I did find another reference to an early 70's Hitachi which do not match
with the Penncrest model seen on the pictures. I include pictures of the
only two known models of Hitachi TT sold back then -- early to mid-70s :
Interesting that there was one (1972) "more Sanyo-looking" from what we
can see regarding the control panel design. However, much different from
the definitely Sanyo-based JCPenney seen on that thread.