1970 Inter C1300 Master cylinder bore size

Guys, anyone have the good oil on the brake master bore size? I've been told 1 1/16 " but I cant even find a rubber kit in that size? worst case Ill take it off and dismantle .
EDIT pulled it apart its 1 1/8"

T68, my 68 ACCO needs braking too, my brake experts says ya can't tell by pulling the plunger out, you must take master cylinder out and in my case give it to him, as there are 3 sizes I forget the numbers but each is only a poofteenth different. My mane has change over and parts as required. I just gotta get unbusy.

yep measuring the bore best if there are multiple sizes, sometimes the rubber seal has the size molded into it as well.

The bigger trucks are all 1 1/2",dont recall the 1300 size .Wasnt hard to get tho ....What normally happens with master cylinders is they get a ring of rust round the outer part of the bore where the wiper rubber sits ,and causes them to drip fluid on the cab floor.

that would be the reaction between iron and the aluminium piston with fluid full of water. Its why flushing fluid is a good idea.

In the past Ive relined master cylinders with bronze bushes from Bearing Service.....the thin stainless tube the reconditioners use is unobtainable outside the trade,for some reason......but I admit I havent tried the net lately.