Im wanting to change my key to a mk3 key as they look cooler and you can put the vrs bage on the bottom of them, is this possible? 

If the key itself has the same immobiliser unit inside and the key is the same shape and size then don't see why not? Got anyone local who can code a new key for you to see? I would be interested to know if you can  

It is I’m getting mine changed soon. 

I just changed the casings over to the mk3. You need the right type though.