I have a SigTac Rangemaster that I got on eBay some time ago. It is a great knife and I have put it to good use. I was informed today that the knife was originally made by Lionsteel in Italy. I would like to know if anyone knows if Lionsteel would refreshen this knife? If not, would I be able to replace the washers in the knife myself? I absolutely love this knife as a workhorse knife and would like to ensure that it keeps working for many years to come. Any information at all that can be provided would be great. 
Thanks!

Thanks!