O-ring kit for Gen 1 .22 cal Marauder Air Rifle.

My Gen 1 .22 cal Mrod is three years old and I've ordered a Lane MK8 Regulator for it. From what I'd discovered the MK8 regulator is Plug and Play, so to speak.

I saw on You Tube where one guy, after degassing his Mrod, had developed an air leak when he aired it back up.

To fix the leak, he replaced the o-ring on the rear of the gauge block (the o-ring somehow got messed up when he degassed it).
Here's the video I saw -

Here's my questions:
1. Does my Gen 1 Mrod use the same o-ring kit as a Gen 2 Mrod?
2. Does anyone know of a good source where I can buy an o-ring kit for my Gen 1 Mrod?

Thanks
Bobby