Marlin Ballard serial range for guns marked "Marlin Firearms Co." ended somewhere in the 37,000 range. So very likely to find a 3 line cast action in that range. And a #3 is the most common type action I see in the 36,000 and above range.
The 2 or 3 line doesn't always tell if it's cast or not. But over 98% of the 3 line addresses are cast actions. There are a number of 3 line address Rigby Ballards found in the 18,000 range, and John Dutcher said he thought the 2 line  rollstamp was broken and they simply used a 3 line until it was fixed. I own a 3 line Rigby in that 18,000 range that is forged.

Forged actions were made extremely early in the first year of production. The Model #1 was a cast action, but the Model #1 1/2 and Model #4 were first offered in 1875, and both were forged actions. They were available in .40-63 Ballard and .45-70, but the #4 was later offered in many more calibers.
I have a #4 that's serial number 4xx. I also have a couple #6 Schuetzen in 5xx and 6xx. Lots of various forged actions were introduced by Marlin the first year in 1875.
The #1 was the first cast action that same year. But the #2 and #3 were also offered the first year in 1875, and all three were cast actions. The #1 is most commonly found in .44 Long, or Extra Long, but I've seen them in .38 XL also. The #2 is most common in .32 Long and .38 Long, but also came in other calibers after the #1 was dropped like .44 Long, .44-40, .32-20. The #3 was almost exclusively .22RF, but the .22WCF was offered, and I've yet to see one in that caliber.