You can get nitrated cartridge paper from Shiloh, but it's expensive. I suggest you make your own (which does not have to be nitrated, by the way). I'm using tracing paper from Office Depot, which is stiff enough to be easy to work with while still being light enough to burn well during the combustion process. If you have the cartridge making kit, you use the mandrel to form your paper tubes and hold the paper together with a simple Elmer's Glue Stick. I'll post some photos after I finish typing.
For bullets, I suggest you make your own. The Lee hollow base Minie bullet works well in the .54, and the mold is both inexpensive and easy to use. To be quite frank, there aren't many options available in pre-cast bullets, though there is some guy on Gunbroker who sells the .54 Ringtail bullets in boxes of 50. I know nothing about the quality of these. It took me two years, but I finally found a ringtail mold for my two .54 Farmingdale rifles--one carbine, one military rifle--but again, the Lee Minie works well. Just make sure you cast the Minie bullet in pure lead, as it is somewhat undersize and needs to be soft to expand fully into the grooves. If you'll look through this 63 forum you'll find quite a few posts about making cartridges. This isn't the busiest section of the Shiloh Forums site, so you probably just need to scroll through a few pages to find lots of info.
These are flat based paper cartridges with the Lee 415-grain Minie bullet.
This is my work table while making up some cartridges using the old CW cartridge paper and the flat pointed CW/Shiloh "Buffalo" bullet like you have. I use the dental floss to tie the bullet into the paper cartridge. The aluminum mandrel is a later version from the cartridge making kit. The other one I have is probably homemade and looks like Delrin/nylon; it makes either .54 or .58 caliber cartridges.
Here are two of my molds and the bullets they make. I have a mold marked Shiloh but manufactured by Rapine, along with the hollow base mold from Lee.
These are some of the boxes I got with my carbine a few months ago. At one time you could actually buy ammunition in ten-round boxes! The Minie is identical to the Lee offering as far as I can tell. The Lee mold costs something like $25.00 plus shipping directly from Lee.
Last but not least, these are the "ringtail" bullets loaded into paper cartridges using the current nitrated paper as sold by Shiloh. The ringtail was the bullet used most in the Sharps rifles and carbines during The Recent Unpleasantness (the "Civil War" to Yankees). The rebated base was used as an attachment point to tie the bullet into either a linen or paper cartridge.