I have used external ink systems for a long time on HP printers and some Epsons.
Get a system with good quality construction: Use Google and Ebay as resources.
You really want a "sponge-less" system as the others dry out and become really problematic.
Here are a few websites to get you going. The first website, CuteMaker, is in china -- you can order direct from them. You have to wire the money first but they are so cheap and they are reliable. As for "Lily" via the email
cutemaker@gmail.com -- you can tell her I sent you as I have bought from them in the past -- this is a big deal in Asia -- My name is Dante.
http://www.cutemaker.com/
http://www.inkrepublic.com/Products.asp
http://www.inksupply.com/index.cfm
Let me know if this info helps, please, send me a private email or email me at
dante@creativebeans.com.
Thanks,
Dante