Jakarta is a long way from Newcastle!
There are a few shops around.
The best one IMHO is The County House on Westmorland Road, opposite the Centre for Life.
Other shops nearby that have decent stocks of car stuff are Phills Models in North Shields, and Model Active near Chester-le-Street.
You'll get a full list of shops in the North East by looking here
Online RC shops in the UK - I'll do a blatant plug for ourselves - www.rc-direct.co.uk
- and let someone else tell you about the others!