Hi Mook, not sure if you use ebay but its worth a look now and again as you may come across the items you need in dribs and drabs which makes it a little more
affordable and can be bought over a period of time.
There are even complete set ups now and again, though these would require collection due to there frail nature but worth it if the price is right eh!
Have you any thoughts on exactly what you want in way of steam plant! there is a vast array of quality plants out there, ACS Engineering for one and then John hemmens
which has been mentioned, if you are really feeling flush this christmas have a look at Stuarts site who have launched something from the Cheddar Models Stable....the list
goes on, so have a look and decide what type of engine and boiler you require then do some window browsing which I think is the best way to relax and take in what is on
the market ok.
Enjoy your new venture into steam, here's to a few burnt fingers and an oily hull too!
Full steam ahead
Cliff