You don't need UKARA for 2-tones, most people are happy with 2-tones, just take your parent to a shop, say "i want that one", job done.
Do not pass GO; Do not remove the 2-tone from the gun you have bought.
Though really, go play the game first, one of the purposes of UKARA is to ensure that only REAL airsoft players and a few select other groups can purchase/make Realistic Imitation Firearms (RIFs).
If you have a relative with UKARA, you should ask them first, anything someone on here might say is moot until you do that.
The answer to this question is in the 9th, 11th, 14th, 21st, 25th, and 43rd posts in this thread.