Some small GSR conversions that come to mind
you could take a railroad J72 and try and turn it into a GSWR J10 by chopping off the cab and replacing it with an ivatt style one
not the greatest detail wise but I have GSWR 90 done using a terrier chassis and a 3D printed shell
the GSR had an 0-4-0 peckett on there books, purchased from the allmans whiskey Company in 1930. Don’t think it left cork though! Horny make it and all you’d need for it to be prototypical is buy the works green version, weather it, and slap plates on either side.
there is a beautiful RTR J24 model out there from 00 works. but it’s very expensive, no DCC, prone to failure (mine has twice). Also never left cork area as far as I know either
A freind of mine and myself are still working on a completely 3D printed Bandon Tank. But thats nowhere near ready for running.