Yes, by all means you can. Just be careful because some manufacturers use corrosive primers. Just be sure to clean and oil your gun each time and you'll be fine.
I wouldn't chance it, the difference between .223 Rem and 5.56 NATO is 20,000 psi of chamber pressure. With the 100 being a collector piece, I wouldn't take the risk of blowing the chamber or any other catastrophic failure. The NATO rounds have considerably more chamber pressure than the SAAMI rounds.
Serial number.
Winchester 70 225 is worth around 1,000 dollars if 100%
I have seen the priced $450 - $525.
If the serial number is above 92000, it was made in 1965 or later. The serial numbers run from 1 ~ 263170
Your winchester model 1894 was one of the first 100 rifles made in 1964.Thus it is not a pre-64 model 1894 winchester.
100 rounds to 100.
95 rounds to 100. (94 rounds to 90).
Being that it is a 1964 vintage gun, it is worth somewhere in the $100 - $200 range.
The recall was because of a wrong size recoil spring. the shot guns recoil would break the buttstock after about 100 rounds.
100-1000 USD or more
100-1000 USD depending on specifics