The extractor from a Swedish 1867-1889 Remington Rolling Block converted to 8x58 R has an extractor that is perfect for your 45-90 or 45-110 or a 40-65.
When they modified them in the 1890s they put in a new hammer, rolling block and re-cased the receiver.
They also had the straight extractor upgraded to a circular extractor.
Most of the converted rifles were stored in a warehouse and never used after this modification since the Mauser 96 came out. 
They are excellent quality receivers and are great to modify as a custom black powder rifle.

(You need to Login or Register to view media files and links)

Steve Holborn (Ontario, Canada) sells these converted Rolling Blocks.
Picture of a .303 British or .30-40 Krag extractor Steve made for my .38-50 Remington Hepburn case.

Thanks for your reply. I will use the info that you provided.