Ricoh Japan will not sell charge rollers seperately as it would lose them money so i doubt if you will be able to find a supplier. as for removing the coating, Ricoh direct engineers have been asked to try this for quite a while with a good results, we have also been told to remove the cleaning roller as well. this method has also been tried on mpc3300 4000, 5000 with good effect but you must leave the lube bar in. vac out unit and remove the layer of the charge roller with ipa and a scourer. main side effect is it will wear out the surface of the drum quite quickly but it is worth it to get 40% more life out of the drums.
I have had some success, some failures with "modifying" the charge rollers. Here's my advice from experience:-
1/ If the customer is running any kind of heavy coverage work with some regularity expect a recall, especially if you are removing the cleaning roller.
2/ Remove the cleaning unit (2 screws on MPC2500-4500, 2 screws and clips on MPC2800 - 5000 and comes out with the charge roller assy) and check the amount of lube bar that is left, if the lube bar is gone then the drum isn't going to last much longer. I always clean the edge of the cleaning blade while I'm in there especially if there's visible toner residue on the drum surface.
3/ I've stopped removing the cleaning roller now as I was getting recalls, what I do now is carefully place them down the rubber hose attachment on my vac one end at a time whilst it's running. This gets rid of 90% of the toner and lubricant that they are saturated with that contaminates the charge roller. Problem being is that they are so fragile and easily damaged.
4/ Change the dev at life, this helps to keep the toner levels going through the drum unit at whereabouts they need to be.
5/ Try and impress upon your boss that this is not a magic fix that works all the time. I had this pushed upon me as some kind of "miracle cure" that was going to save the company megabux, cure world hunger and save the rainforests. It works most of the time and can get you a lot more clicks out of a drum, but I've heard ridiculous claims of supposedly getting 400k out of a drum with a PM life of 80k, double life is usually do-able (160k) at 200k I've found the lube bar is practically gone and by then it doesn't owe you anything anyhoo.
ok, crazy idea, i've been doing this a couple months now and so far no problem...this only works with the "green"-ish charge rollers:
take the white cleaning roller out, then carefully, VERY CAREFULLY, scrape the "green" coating off of the charge roller (best to use a knife, stuff comes off like "lottery ticket" scratch-off stuff). get it down to the white core, then buff out any remaining spots, etc with some Scotch Brite. make sure it's all clean then pop it back in (leave the cleaning roller out).
i'm also looking at removing the lubricant bar from the Transfer Cleaning unit as that seems to be the stuff contaminating the charge rollers. you have to leave the Lubricating Brush in tho as that is part of the whole drive for the Trans. cleaning unit.
i haven't seen this idea anywhere else in the forums so i assume i'm the only one thats tried it, but so far, so good!
I need to amend my post in regard to the technique of removing the coating. don't use a knife/scraper (unless you have to).
I've found that a Scotch Brite pad and some alcohol (rubbing, not drinking ) takes the coating off very easily and leaves a much smoother finish to the charge roller.