Not nearly enough information to be able to give you any type of reasonably close estimate.... There were many types - variations of enfields made and for a long time. I would suggest going on line to one of the major Gun auction sites and try and find guns as close as possible to yours and see what they actually sell for .... (read not just what people are asking for them). You can also google it and you should be able to determine a good amount of info that will help you in determining a real price.
If Thompson Center is America's Master Gunmaker... We are in alot of trouble