I'm considering purchasing this head. Would appreciate the experts opinions.
Apparently an RS2000 head. I'm not aware of any difference though, maybe even German RS2000 head?
Does it look stock or not and would it be a good starting point for an engine build?

The date of manufacture appears to be 1972 however can't tell for certain from the photo.
So would have been fitted to any cars manufactured in 1972 or 1973.
Hope this helps.

Thanks PeterM.
So clearly not off an RS model. Probably cortina engine if its 1972 or1973?
 
Anyone have a comment on if it looks original and good as a starting point? I've seen some comment son Facebook threads about bad porting jobs. I want to make sure i don't get a dud, any help appreciated.

All things considered with two old heads in the same condition and for similar $,  an 'EB' head is the one to choose. In your pictures I can't see into the shadows to see if there's an EB casting mark on top. Same goes with old blocks, go with the 'EB'.
SFE 

Doesn't the Ford casting number 84HM9809DB indicate that this casting revision in anywhere from 1984 onwards??

It is 84HM8090DB.
Not sure if that changes anything?

I was thinking along the same lines as MK1_oz, in that the 84 casting number means it was post 84. I have a head here that starts with 74 and has different letters (UA) on the end and it has slightly different shaped chambers. mine was from a mk2 escort originally I am told.
whatever you get, you should crack test it. they need lots of work regardless of what they are from.

Post 84 means it can only be a Sierra head??
 
(Sorry I tried to remember the casting number after looking at the pic and got it woefully wrong!!!!)

If it was a Sierra Head wouldn't it have the tear drop inlet ports for the fuel injection?
 
I don't think the 84 has anything to do with the year.

I just copied and enlarged your photo and removed shadowing.
The head was manufactured in 1974 as per casting indicator. (not 1972 as I first thought)