Fingers crossed it'll cut ally

[Fivetide]

What do you want them for?

Could you not use a length of o-ring material?
You can buy kits for making o-rings, which are essentially a length of round rubber in rubber/viton/whatever spec, and some glue/bonding/vulcanising stuff.
I'm sure you can probably get lengths of square material aswell, which would be far better than oil soaked seals.

I bought a set of o-rings but because they are round and the rubbers fairley hard you dont get enough surface area for the vaccum, it tends to role across the rubber, my larger rubber ring is flat and compresses under the force, the o-rings dont :(