That will be totally based on the model of Winchester in question,and the amount of original finish remaining on the Winchester in question.You will need to provide this info to get a answer to your question.A serial number will also help identify if your Winchester was made in 1951.
If you truly have a Winchester Model 1906 that was manufactured in the year 1951, it would be priceless or absolutely worthless. Winchester ceased production of the Model 1906 in December of 1932.
Your Winchester model 61 was manufactured in 1951. Reference for Winchester rifles can be found @ http://armscollectors.com/sn/windates.htm
1951
Your Winchester model 1897 shotgun was made in 1951.
The gun was made in 1951.
Manufactured in 1951
Manufactured in the year 1951.
1951
50-500 USD or so
Winchester Model 94 serial number 1771777 was manufactured very early in the year 1951.
Your Winchester was manufactured in 1967. The value will be determined by its condition, but won't be more than about $300.
If this is a Model 94 Winchester (because they made other models chambered in 30-30) then it was manufactured in 1950 and has significant potential value, depending on condition and any factory features. You would be well advised to obtain a professional appraisal.