The lovely chaps at Steam Workshop have got this tidy new 1" Minnie available, I'm sure they'd be happy to commission it for you if desired.
http://www.steamworkshop.co.uk/portfolio/minnie/
Might be a bit expensive for you as it's so new - don't know what your budget is so you may be pleasantly surprised!
Simon is a lovely bloke and will be happy to hear from you if you're interested - feel free to tell him I recommended you.
He may have other small scale traction engines in stock or coming into stock shortly but not advertised on the website yet, so do ask if he has anything else even if the 1" Minnie above is out of your price range - you never know! His number is 07816 963463.
Good luck on your search, whatever you end up with I hope you like it!
