Hmmmm. Are they the original aglets? It may be worth it, then.
I had the aglets replaced by EG in Northampton in the early 2000's before they became collectable. But isn't that just servicing?
Lange actually reduced the size of the 1815 this year from 40 mm to 38.5 mm (how often does that happen nowadays?) It's more "smart casual" than "dress" with the blued hands and small seconds treatment, in my opinion, but still a lovely watch.