I got the Dramm stix risers and pin perfect nozzles from Growers Supply. They are a distributer for Dramm products. You won't find them on the site, you will have to email them. I think I had to buy five or ten of them at a time. I use three of them in each propagation bed for good coverage. Don't worry about the GPM, these nozzles make a very fine mist and that's what you want for the soft wood cuttings. I've had good success with 10 seconds of mist every 20 minutes.
Here is a link to Growers Supply, Just email them with what you are looking for. They are very helpful. Growers Supply
Hope this helps.