When I got my Model 8 I wasn't aware of the brass/ammo issue. I did find a box of ammo eventually, and a member on thegreatmodel8 sold me a bag of brass. RCBS had the dies.
The .30 Remington is a *nice* little cartridge. Remington made little effort to promote the .25-.30-.32 outside the Model 8/81 line, though. The only other rifle I know of chambered for one of those was the Model 30, which was a civilianized P17 Enfield. The petite little .30 was probably lost in there, considering the P17 will swallow .505 Jeffrey or .577 Tyrannosaur...