Any gun that needs the barrels replacing either by new barrels or sleeving is a prospective candidate . How ever it is the man who will carry out the work who must make a final decision and that can be based on several factors . Such as the profile of the old tubes comparativly against that of new tubes available ,so unless you have tubes custom made which could efectivly double the cost of the job ,the out come will not be satisfactory to either him or to the customer . Non of us want to put our names on work that we wuold not be happy with . For this reason alone I have turned down many thousands of pound of work over my working life .Like all work it can be done if the price is right and the risks are accepted by both parties but unless you actualy do the work your self you can only be guided by those that do . Problem is that there are many dealers in all countries that do not full comprehend what is practical and what is not .