England sucks noodles doesn't it?
Keep searching eBay, I buy a lot of my stuff from there but you have to search frequently. I also bought my Kidrobot figures from dinkybox.co.uk - I've emailed them and asked if they could get more Futurama stock, so maybe if you and others email them too they may make it happen. They are a friendly little company so you should at least get a response.
The only other suggestion I can think of is Forbidden Planet as you already know. I asked a similar question a while ago, and I'm still looking
You may find a specialised real world shop somewhere, but I have yet to find one
Let me know if you find anything