.307 and .56 WCF jump to mind...
Where would you like to start? .30/40 Krag has been necked up and down --regular shoulder and improved-- and is remarkably like the .303 British. Krag is not strong enough for much, but single shots and P14's "Katie bar the door..." Cases are awful close. In USA, Krag has been used in single shot rifles for about everything, and the .405 Winchester (there was a .35 Winchester that died aborning, same case in .358)... .405 WCF is a .30/40 case a trifle longer and necked to .40. It worked at the "new" circa WW I era, pressure of 45K CUP like the also new .30/'06. Chambered, for one, in the new model 95 Winchester lever action. (Pres. Roosevelt, Teddy liked it in Africa, or so he said many times. 03 Springfield too.) In Canada Mr. Epps, gunsmith, (Elwood Epps, gunshop still running, don't recall the exact e address) worked with the .303 British case, necked up and down. I think his biggest was .338. Regular shoulder and Improved. Little lame in SMLE and hot, hot, hot in P14's. [ AND he had a .303 Canadian Magnum which was the P14 enfield (made in USA by Remington, Eddystone Remington, and Winchester--.303 bolt face and belted mag is same, eg. .300 H&H)... p14 re chambered to the .300 H&H case and necked for use of .303 caliber bullets... not exactly rimmed, but there is a rimmed H&H case they used in double rifles.]
I assume you have studied the Improved .30/30 which reportedly equals the .300 Savage, another .45K CUP cartridge. It, the .30/30 case, has been necked up and down. .38/55 is the same case and a little strengthened and higher pressure re introduced as the .375 WCF. Newest to family, 7 Waters, I think. Getting old.
The Triad series is available,( web search), .444 Marlin case necked down to use .308 dies (or 7/08 or .358WCF) to reload the rimmed case for single shots. TC's common. Little bigger and came out before the .307 and .356 Wcf rounds.
Mr. Ackley put out a two volume set of books many years ago, available from eabco.com, sinclair, ebay sometimes, and others... surveying couple thousand cartridges: -- factory, IMproved, and wildcat. I recall someone took the .348 WCF rimmed case and used it for various things. .30 was popular. Even turned the rimm off to make it rimless. In the Win lever 71, it got taken up to .458 and .500 for Alaskan bears at close range. THUMP!.
If I knew what you planned to shoot at, I could be a bit more specific. De Hasse on single shots mentions many of these mods to Win single shots back when they were not worth much. Everyone wanted a repeater...!! luck