Injector questions(NOT A DEBATE!!!!) Nothing to do with size! lol

[scourge at cogeco.ca (Scourge)]

Hey all.
I've started looking around for pricing on some new injectors for Blacky(2.0L ABA w/JH head). The first place I talked to told me there's three different P/N's for 8V CIS injectors. But the years break down weird.
76-84 is 049 133 551A $30 each CDN
85-86 is 026 133 551 $70 each CDN
87-88 is 035 133 551F $80 each CDN
Now the 1.8 JH came out in 83 and AFAIK didn't change during the years it was in use in roccos(I don't want to start the whole hydro vs. solid debate again). My 86'(That's blacky) had a solid lifter head, now he has a solid lifter head from an 84'(that's just what I had around to rebuild). 
So I'm confused, I can see different injectors for the 1.7 then the 1.8 but what would they change from 84 to 85???  As you can see there is a HUGE difference in price from the 84 to 85.....why??  lol
If it makes any difference, when I have the head rebuilt I got new injector seats(the old ones got trashed when the shop took them out). The old ones were plastic and the new ones were brass. I'm not sure how the whole air shrouded thing works, but these seats were just stubby little things, maybe 1" -1 1/2" deep. and the injectors only have one rubber seal.

Help!!

TIA
-George