Dont be scared of it. I just changed mine, got it from signs in china from their site where they have a better price than ebay and new customer coupons too. Its a genuine epson head made in japan, my guess is these are sold to a chinese OEM at a manufacturers price who backdoors them and not supposed to be sold as parts (the reason they pull the head rank off). They will email you a head rank no charge but Ive read that it doesnt even matter. Not sure if its true but I changed ours to what they sent us anyways. The worst part was dealing with a couple tiny metric screws with stripped heads. I skipped a bunch of steps the manual said to do, I pretty much unplugged it, swapped it out, did 1 cleaning, aligned it and went to printing. I was super lazy. The manual says to adjust the yellow/mag head against the black, i wasnt going to deal with more baby screws so i just did the adj on the black head which was replaced. It prints like new. If youre familiar with head adjustments on the printer itll take an hour or two start to finish, a little more if you havent done it before. Save the $600 labor, its not rocket science.
For calibrations theyre easy to do, IIRC theres 2 manual ones and 1 in the menu. It just does a test print, turn the adjustment knob and test print again. Dont overthink it, its very basic just a little time consuming doing it little by little.