You won the OC3D gear right? In that case tell her that part of your contractual agreement with OC3D when you won the prize(s) at i40 were that you was not allowed to sell or swap the components given to you by us for at least 1yr (technically there is some truth to this!).
The reason for this is that most components were imported into the UK as 'product samples' and therefore no import duties were paid. Selling the items for a profit is therefore illegal and would at minimum require you to pay import duties and VAT on the items.
That should put her off