The review says the 1928 type and that hornby making them and goes on about the massive colour difference between the 2 types, the picture appears to be of a flat sided hornby pullman as opposed to the matchwood ones. It also suggested the older hornby type may be a closer match to bachmann's colours. I'm no pullman expert and have got rid of one of hornby's latest pullmans due to it derailing and not coupling properly to anything else.
However I have found several pictures of them in the book Treacey's British Rail they again aren't all clear, focusing more on the loco than the rolling stock but they again suggest the flat sided type, interesting selection of motive power too, we have
D0280 Lion on the Yorkshire Pullman from Leeds Central to Kings Cross,
class 46 D177 again on the Yorkshire pullman, this states it had 6mk1's with a 1928 brake at the rear,
class 37 D6813 on the master cutler Sheffield to Kings Cross,
class 47 D1519 with the White rose pullman from Kings cross to to Harrogate which split at Leeds with part going to Bradford.the above service apparently replaced the Queen of scots service and there is also a picture of an unnamed D9010 hauling that service again with mk1's and an older brake,
and finally a picture of D9017 in a somewhat heavily weathered state departing Kings Cross with another Yorkshire Pullman service.
All the pics are from the early to mid 1960's and perhaps the most interesting is the picture of Lion which might be something a bit different. however it was only briefly used for a month or so prior to withdrawal in October 1963.
Hopefully that has been some help and indeed has helped me make up my mind to acquire a few more than the 1 I already have being as how they were used in and around my patch so to speak. Not too sure about suitable end of the line steam haulage though possibly A1 or A3 maybe even an A4 might be acceptable.