I don't think the shocks were the same as the 1 used an AMP rear end, but the 2 was Mongoose's own.
Either way, I may have one spare in the near future, though what is wrong with your one (if you have one)? They are pretty simple to take apart and repair if you have a seal kit, and I have one of those too, as just received some bits direct from AMP.
If you can wait, I've just bought an amp that comes with a Risse shock and a spare standard shock. Not sure if I want to let the spare one go, or what condition it is in as I haven't got it yet, but once I receive it, I'll let you know.
Ian