Identifying a cylinder head

Hoping someone can help me here. I'm trying ot identify a head for a friend of mine He describes it thus:

"The no stamped on the rh ex is FBS on the head is a Birco stamp it has a no 06-038C and has a round stamp wirh 587 on it.
Inlet measures 32mm and the inlet valve is 37mm. I can not see any further markings on it"

To me this sounds like an early 750 Commando head, but I'm not sure.
Anyone?

Cheers,
Steve.

Not sure if its possible but the FBS stamp could be Fred Barlow Spares.
He was an engine tuner/ builder and lived in Staffordshire. I had a head worked on by him, thats what he stamped on it.
If it is the work will be good.
Hope this helps.
He was a Triumph (I believe) development engineer.

In the early 1990s I took an 850 engine and gearbox to Fred Barlow.
I dropped it off on a Monday afternoon and picked it up the next Thursday, completely rebuilt, bead blasted, gas flowed, shot peened, blueprinted, etc.
He used to work for BSA on the works B50 motocross bikes (Jeff Smith). A very friendly person and a true craftsman. He died from cancer in 1998.
His shop was in Tamworth next to the Reliant factory. On the other side of the road used to be Devimead (of the famous BSA 750 cc and crankshaft bearing conversions).

modified 68-70 750 head which never had 32mm ports stock on a standard commando
http://atlanticgreen.com/nhth.htm