Unusual design!. it's based on the Archemedian principle. A bit of searchng Hose manufacturers may well produce what you need.
One point about these is that with rubber involved, there needs to be a method of priming with water etc prior to starting up from a dry condition.
As for makers info, It may be worth enquiring with the company. Yes, it look's like they are still in business. Here's a link to their 'Timeline' on their website- MONO PUMPS Ltd
Good luck.
Regards
