Hi Craig, In my opinion, there will be no probs at all with this solution, mate, as the end caps will still fit, and the extra weight will actually possibly be an advantage. The Model 17 "Supercut" has a solid steel front roller, and is really heavy, and does its job well.
If you were really concerned about the outside diameter, you could take it to an engineering workshop and have 1.5mm spun off it. With stainless steel, you can polish it to a mirror finish if you wish.
