Digital BW, The Print

I am located in the Uk and have used Lyson neutral quad black inks on an Epson 1160 for some time now. The  1160 I am using at this time is only about 1 year old, I bought a brand new one on ebay to replace my previous well worn printer. On ordering to restock the black ink today I discover that Lyson have discontinued this product. I did manage to obtain one 125cc K ink to keep me going for a while. I use the quadtone rip software to do my printing and am very pleased with the results. So what is the best plan to replace the inks when my current bottles are depleted. Can I replace the individual ink channels with another manufacturers ink, like MIS for example. Can I obtain any of these alternative quad inks in the UK ( no luck with google searching for this answer so far). I would appreciate ant advice and suggestions the group members may have to offer.