Alternative rims/ shock bottom retainers

[jpmatrix]

1. What other rims 12mm hex have the same offset for the front and rear?

I do have a load of redundant 14mm hex rims just wandering is there any way of modifying or getting an adapter to fit in the k2.

2. I do have a load of Losi and ae big bore springs.is there a shock spring retainer I can buy so I can use these springs?

Thanks

James