I've lost the arial off my phone (moto v525), it was broken anyway and it must have fallen out.

So i need to get a new phone. I have one of the o2 sims just now but i can change. I like flip phones. Before i got the o2 sim i was spending about 20/30 quid a month on top up's but i still cant get a contract one apart from very cheap ones but only if their worth it.

I'll have about £100-200 to spend

So has anyone got any ideas? Would it be worthwhile looking to get a phone from somewhere else -ebay or something and just puting my sim in?