Trapdoor Rifles

A rifle I’m looking at online has a second oval style ESA with date cartouche, but the serial number puts the date in the year 1890 range. Is this viable, or has something been fiddled with?

Two possible explanations:
1- Gun has original parts as assembled but at some point the cartouche was removed (common in post SAW "clean and repair" refinishing) and Bubba got a stamp off eBay and "fixed" it, not knowing that different cartouches were used at different times.

2- Cartouche is original to the stock, but stock got switched on to a newer action at some point.

But, there is NO WAY an early cartouche would have been armory applied on a rifle assembled with a much later serial number.

Remember, it IS POSSIBLE for early serial number receivers to show up on rifles assembled much later, and quite a few of those are known and accepted as anomalies, but legitimate.

Yeah, the cartouche shown is not very legible, and that is a concern, too. Bummer.

Well, if it's not very legible, I'd put my money on John's number two. After 55 years of trying to sort the wheat from the chaff, I can say, with conviction, that the 90% interchangeability of trapdoor parts is at once both the blessing and the curse of collecting them!

So, all that being said, and thank you, should I consider this one? I’m not a “collector” per se, I want to shoot it—but I do want one that’s not just tossed together and/or faked. The rifle, as a whole, looks to be in very good shape.

Should you only want it to shoot and not for collectors value than go for it, as long as the price reflects that it's a parts rifle.
Myself, I'd rather have a rifle that's correct even if I plan on shooting it.
Just my 2 pennies