Stanier Suburbans from Dapol

[Roy L S]

I could feasibly use these for the 'Newport Nobby' but then, how the heck do I get it into either of my layouts when it only ran between Wolverton and Newport Pagnell?

Rule 1 is always your friend Mick!

Way too much of a stretch, Roy, unless they could have appeared on the Varsity Line in the late 50s/early 60s

Buckingham Branch maybe? I seem to recall it was DMU from Verney Junction to Buckingham but a separate steam service from there to Banbury until that section closed to passengers, still a stretch true, but...

[PLD]

Excellent choice - accurate non-corridor stock in general has been a big obvious gap for a long time!
Just to note though, the LMS didn't refer to these as "Suburban" coaches (except for the non-standard dedicated North London sets) - the official description was "General Service Non-Corridor Stock", and they certainly weren't confined to suburban service - they could be seen all over the LMS system, including many rural branch lines.

The ones described as "Composite (Push-Pull)" from the running numbers look to be Diag 1921A motor-fitted intermediate coaches. i.e. have the through pipework and electrical connections to go between the Loco and a Driving Brake-Third, and are NOT a Push-Pull train in themselves...

The Ivatt 2MT is ideal power for the Push-Pull sets post-war, but there is currently a lack of a suitable loco for pre-war though... they mostly worked with older pre-grouping locos such as various Midland 0-4-4Ts, L&Y 2-4-2Ts and LNWR Coal Tanks (unless Dapol have something suitable up their sleeves )

I'm definitely in for a set to represent the only Named Push-Pull train - the 1950s "Welsh Dragon" formed of a Driving-brake 3rd + 2x Motor-fitted Composite + Ivatt 2MT.
Maybe an LMS Push-Pull pair and another 3/4 coach set as well.