Hi, that boiler will likely work, but, in Australia you can't use it at club meetings, or in public unless the boiler is copper. Most of those little cheapies are brass boilers. I don't know the legalities elsewhere in the world.
I too am trying to find a model Sternwheeler large enough to steam power. The Mark Twain looks good, as does the Dixie Queen, but I've never seen a kit. Maybe this would be able to have a steam plant squeezed into it?
http://www.cornwallmodelboats.co.uk/acatalog/occre-mississippi.html. Maybe I should finish my Imara first, but to do that I'll have to start it I suppose.
.
I'm like you, I like all the bits on hand before starting. I have purchased a new boiler plant from John Hemmens in U.K. If it's half as good as the other items I have purchased from him, I'll be very happy. It is due tomorrow.
I have a dozen or so boilers, and many more engines, but, I'm not too sure I have any with a stroke long enough for you, else I'd be happy to help out.
Maybe the Stuart S50 would be ok. That's a very sweet engine, has quite a long stroke for it's bore, and loves "just ticking over". Not too pricey either.
I hope this helps.
Steam Head.
