I really need to confirm the RB that appears to be a 1870 Army Trials. Everything is correct except the barrel is 32 5/8 in. Possible barrel change to a near same 1871 Navy. The rawhide barrel repair is still solid. I have a 1870 Navy whicvh is also 32 5/8 barrel. And a several NYS RB's. My main pusuit has been short rifles and Carbines. With a Baby in 44 WCF and a 46 RF in a Uraguay carbine. I reall want to get some guidance as to the direction to go with over 40+ Rolling Blocks which I  reload for many.  I have 3 Swede RBs including a rare short School Training rifle in now relined 44WCF. Several original 8X58 Rim Danish that are great shooters.

A rifle like this was discussed on the Remington Society web site 2 years ago.
Here is a link
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Have a Good Day,
Matt

Congratulations on acquiring a very rare rolling block.
Owning 40 RBs puts you in the category of having the virus for which there is no cure.  If you do not already, you owe it to yourself to have Richard Hosmers' book, the .58 and .50 caliber rifles & carbines of the Springfield Armory 1865 - 1872, in your library.

The trials rifles were made on the design of and the raw/basic parts for the 1870 Navy .50-70 Rifle. The intra agency jealousy between services had already shown itself with the RB pistol ammunition. The Army insisted their .50 pistol cartridge be different from those already manufactured round for the Navy RB pistol. Hence the Navy .50-25 and the Army .50-26.   
As you know, the Army insisted on changes to include adding the safety lock system. Which I might add Remington quietly abandoned after the New York State contract of 1872.

Anyway back to your rifle, the barrel, forend, sights match the 1870 rifle parts. That being the foundation of the trials rifle, it is not surprising that trials rifles with these features exist.