Hardox is about the cheapest armour you can get (unless you have a sponsor). It does weigh a fair bit though.

Dont give up now either. Aim for an event a few months down the road and keep on building to compete in that event.

I bought my featherweights batteries off ebay. 2 6v 3300mAh packs and 2 chargers cost £40 (I bought 6 packs so the total cost came to around £80).