Bigger version
here.
Not quite sure how accurate the boundaries are (I drew the outline map myself based on a not-very-detailed-at-all source, so...). Source for the data is Nicholas Whyte's excellent online archive. Some brief notes are probably needed:
1. The UUP was split for this election. The division was between those who accepted that power sharing between the two communities was necessary and those who didn't want to work with taigs. Pro-White Paper is the former.
2. Vanguard was probably the closest thing Northern Ireland has ever had to a genuine fascist party with mass support. Given their success in Belfast in the '74 elections its surprising to see how poorly they polled there in '73.
3. NILP = Northern Ireland Labour Party. The first proper Socialist party on the island of Ireland (originally established as the Belfast Labour Party) and nonsectarian in politics if not in electoral appeal. Traditionally a party of Protestant skilled workers the NILP had already lost most of its base by this point, but still managed to win a seat in East Belfast.
4. The Independent Unionist in West Belfast was the Loyalist activist Hugh Smyth (still on Belfast City Council representing the Court ED (Shankill) for the PUP). Not sure about South Antrim.
5. Republican Clubs = Stickies.