AFAIK printheads for the MX870 are still widely available from reliable vendors.
If you’re in North America, Canon USA is the best source
As you mention €20, I gather that you’re in Europe ?. then Eparts.fr in France or
www.ceins.de ( C1 supplies ) in Germany.
You probably know that new genuine printheads are expensive. Let’s say €65 + shipping in Europe. I wouldn’t know the cost in USA or other areas.
As an alternative option, there’s the ‘Chinese lottery’ on Amazon/Ebay/Ali-Express.
€20 gives you a ticket number with dubious chances of winning. Even if that refurbished unit worked OK in the beginning, the probabilities of failing within a short time are high.
I played myself two or three times without luck. Other forum members here had similar experiences.
As for the total number of pages to expect, this is more a question of luck than anything, provided you don‘t mistreat the printer. Using only OEM ink can make a significant difference as well, because some third party inks, specially pigment black, fail to cool down properly the thermal printhead and the nozzles can be damaged irreversibly after a period of time. On the other part, some well cared printheads used always with OEM inks fail very soon for no apparent reason.
If I mentioned before the ‘Chinese lottery’ now that would be the ‘Canon lottery’.
It seems that Canon users, are bound to end up being compulsive gamblers, willingly or not..
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