I do like odd things - and this qualifies! If it comes with the cab (I'd think so?) - it's a bargain of note... though I'd be prepared to replace caps at some stage.
Some blurb from https://en.tefivintagelab.it/strumenti_vintage/eko-herald-vi/
The Herald VI is one of the most powerful amplifiers that could be found in the early 70s; designed primarily for the organ and electric piano, due to the considerable power it is able to deliver, and the 4×12 case has been widely used as an electric bass amplifier. It sounds great even with electric guitars. It has two channels one of which houses the effects of reverberation (very nice, uses a tank of Accutronics) and Tremolo. The preamplification is solid state, the final section uses thermionic tubes with 4 6550 and 1 ECC83 for a maximum power of 165Wrms.
Check out the facebook ad [here]:
