Similar but not the same. Same colour scheme but different decals and totally different forks. The forks are 'lugless' with a smooth, chrome, sloping 'aero' crown, the head badge is the older Carlton sytle rivetted badge, no decal on the top tube, chromed head lugs etc. It has an F serial number which I understand puts it in the late 50's.
A bit of history: My grandfather and then my father & uncle owned a village bike shop in Northern Ireland, which morphed into a filling station / garage with bikes eventually being being dropped altogether in the mid 70's (I was in my late teens with a motorbike and no further interest in pedal cycles). At that time the entire stock of bike stuff was sold to an equally long established bike shop in the neighbouring town and there is a strong possibility that this was among that lot. It's the type of thing that my Dad would have had.
In the late 80's I started cycling again and bought a Peugeot sports (tight & twitchy, 501 tubing etc), quickly tired of it and wanted something better. I visited the local bike shop and the elderly owner suggested that I could build up this Carlton and it seemd like a good idea at the time. However 23" is really too big for me so I had reservations and it simply never happened. I then bought a used Mercian sports/tourer which I still have and the Carlton frameset has sat in my garage ever since. For anyone from Northern Ireland, this came out of Danny McShane's loft over his old shop in Ogle St. Armagh. At that time there was stuff in there since the Great War.
I just picked up on this thread.
This sounds like a 1970 frame, judging by the serial number.
I have just purchased a used Carlton Professional frame and wondered if I could see some photos of this NOS frame, just to check the decals etc.