Carisma 2000mAh micro saddle packs are available (part #CA14761), but they are expensive (£50), and hard to find in stock anywhere.
The only other option I have seen seems to be packs from 'Smart Teknik' (
http://www.smartteknik.se/uk/lipo-ba...00mah-20c.html), which are also 2000mAh, and only £18.70 in comparison. They are located in Sweden, but the website says free delivery to the UK. I haven't bought from them personally, but I am tempted to get one of the 4-pole motors that they also sell.
I bought a used GT14B a few weeks ago myself, but it luckily came with a few LiPo saddle packs so I didn't have to search around for some.
