Torque tube seal-need a quick fix

[RalphM]

Oil from my rear axle is migrating to the transmission. So I've got the rear axle out of my AV8, I was going to put an aftermarket seal kit in, but the maker of the seal is backed up and I'm not sure when it will be ready.
The weather is just too nice here for my car to be sitting in the garage.
I'm putting it back together this weekend, come hell or high water. But I'm wondering is there something I can do to at least slow down the oil flow.
Like a piece of rubber with a center hole as a gasket or maybe a solid gasket, with a cutout for the pinion shaft?
Anyone delt with this?