I will get some pictures of them and also look for an ident number, I have just found something similar on Nook industries a type FG ball nut with the m20x1 thread and they list 2, one with a wiper and one without so I may have the ones without wipers.
I suppose I could get in touch with Marchant Dice to find the manufacturer.
Thats the trouble with this lark one step forward and 2 back. So far everything that I have tried has ended up by having to buy more tools and then seek the knowledge on how to machine a part.