ok i have my pump apart right now.
that square shaped oring inside the pump...hrmm. i dunno what it specs. looks like the square cut you suggest...but it could just be a regular oring thats been squished over time. tough to say.
i found a bearing that matched the inside andoutside diameters at the store(by chance since they didnt stock much).
wasnt sure of the depth.. i got the one they had and luckily it matches up.
depth of the bearing is 12mm.
so its a 40x17x12
my old one is a bit noisy. figured ill replace it since im in here.
theres also another seal behind the bearing.... its like a cam seal(or diff seal) its not just an oring. i dont have specs. mine looks to be ok and i had no leaks though im hesitant to rush it back together. its ID is 20mm and OD is about 32mm.
Id have to pull it out and take it to the store to find a replacement.
also not sure if i want to run a round cut oring where that square one came out...