How many different loads do you want? If it is only a small range of sizes, buy one of the flasks from Krank's with interchangeable spouts, along with several spare spouts, enought for the range of loads you want, and file them down to size as necessary. I have the standard 21, 24, 30, and I think a35 grain somewhere, all off the shelf. For my .44 Uberti, a 21 grain load with a .451 ball works really well on a 25 yard range. Otherwise, as you say, make up a series of different dippers from old cases. One guy at our club who was carp at metalworking lashed out the princely sum of £10 for a set of Lee plastic dippers, and cut them down to size with a Stanley knife, reckoned it was worth every penny. Whichever method you use, pour straight into the phials, I keep the empty powder flask in my black powder box with an anti condensation sachet courtesy of my local shoe store in it, the various dippers and spouts in a ziplock bag next to it. You pays yer money and teks yer choice as they say. Good luck and enjoy, whichever you do.
"Peace is that brief glorious moment in history, when everybody stands around reloading" -- Thomas Jefferson
N.S.R.A. RCO, Club Instructor, Club Coach.