How about an old HP device? The HP 6216A and 6216C are both 25V, 400ma with adjustable current and voltage. Or you could get the 6218A or 6218C for 50V, 200ma. Or you could get a HP 6234A or 6235A for a dual/triple supply (but neither has an adjustable current limit). All of these are very small and very inexpensive on Ebay.