Oil in exhaust

[Evotrucker]

so today after i picked up the head from the shop, they told me that i had 3 injector cups go bad and that are leaking... great. okay, so the shop has a isx head thats remanded at the shop for 3.5k, sound reasonable? or my other option is the send the head back so they can send it somewhere else to replace all of the injector cups for $900.

also to note, the shop charges 1.5k to clean and rebuild the head, if i have to. the head was rebuilt in the last over haul, so i'm not sure if the head needs to be rebuilt all over again.