The golden key is great, people ask to see it, you give it to them and they're even more impressed.
I wish I could make my own (a little more ordinary) key, if you gave it away at the end of your presentation (implying it's nothing special) the effect would be even stronger. In fact you could even build a reputation with a disposable gimmick of this sort.

I could get old mortice keys but any ideas how I might manage to transform to the final item?

I've never made my own prop before so it's really puzzling me how I could do this.

Billy