The elevation is adjusted with the "slider".
(That little saw-toothed strip of metal that's tucked under the rear sight.
The 'windage' (left and right) is adjusted by moving the rear sight slightly.
This is done by gently tapping the rear sight to one side or the other with something soft enough to not mess up the finish on the metal, by someone careful enough not to ding up the wooden fore-stock.
Remember that moving the sight left slightly moves the hits right a lot.
Go easy, a little at a time, It can be frustrating, but once you get it right, it's good forever.
(or until you drop it)
Start with gunpartscorp.com then eBay and auctionarms.com
Most came with a tooth ramped iron sight.But there could be different styles depending on the age of your Winchester model 1894 rifle,such as a peep sight,a full buckhorn sight,etc.
Your winchester model 1894 rifle was made by winchester in 1908.
your Winchester model 1894 was made in 1900.
your Winchester model 1894 was made in 1909.
your Winchester model 1894 was made in 1911.
Value of a Model 1894 Winchester serial number 491333
Your Winchester model 1894 was produced by Winchester in 1912.
Your winchester model 1894 rifle was made by winchester in 1972.
Your winchester model 1894 was made by winchester in 1958.
Your winchester model 1894 rifle was made by winchester in 1910.
Your winchester model 1894 was made by winchester in 1972.