Looking to purchase a used Diana model 100 and am looking into the availability of Breech seal and Piston seals. Can anyone tell me how long they last typically? And a source of supply?
Thanks

I bought my Mod 100 new about 15 years ago and its still on all the original seals shooting just fine.
I bought a few spares including the breech seal from the Diana manufacturers in Germany about a year ago.
I have not used them yet but I like to have the essentials at hand for when the time comes.

Contact them via e-mail and tell them to quote you a price including postage for the part numbers you need.
Quote the part numbers from their schematics of that particular model to avoid confusion.
HTH
David