Thanks all.
Was really hoping I could get away with an 08 or terrier (expected the Pannier was too long) but oh well.
Think I'll order a sentinel and see how it goes.
Been looking at some of ETS' small locos (the Austerity and S160 are tempting but WAY out of my budget for a single loco) and will probably go for one sooner or later.
Already have a few used kit built wagons and an Atlas/Roco 2ft radius point that I've pushed them through, so know what I'm dealing with when it comes to couplings and buffer lock, etc.