Three digit Model 1894 with mismatched parts|Winchester Rifles|Forum|Winchester Collector

New member here.  A local museum asked for help evaluating a donated collection of 32 Model 1894 and Model 94 rifles and carbines.  About 1/3 of the collection are commemoratives in the original boxes with commemorative ammunition. 

The other firearms range from a 3 digit serial # in .38-55 through relatively recent angle eject guns with safety in new condition.  Although the donor was supposedly a knowledgeable collector, several were mixmasters:  An early carbine with a newer buttstock and steel shotgun buttplate, a carbine with replaced barrel and magazine tube, carbine with a replaced loading gate spring cover, a couple with replaced sights, rifle with replaced barrel that was loose in the action.  

My question is about the .38-55.  The finger lever link, the breech bolt, and carrier are obvious replacements.  The rest of the rifle (26 inch round barrel) would grade very good antique standards with even brown patina, clear and sharp markings.  Wood also very good with minor dings and wear, no missing wood or bruises.  No remaining blue even in protected areas.  The donor claims the rifle was appraised at $6000, and the museum considers it the “gem” of the collection. 

I understand no one will want to place a value on the gun without more information and lots of pictures.  But how much do the replaced parts detract from  collector value?

If there is interest,  I can ask the curator to provide pictures although I have tried to post pictures here before without success. 

Thank you for your time and patience.