Airplan Flight Equipment
http://www.afeonline.com/afeshop/enter.html
They might be cheaper on a few things, maybe a bit more expensive on others, but I've had no bother with them so far, I use Transair as well though. They obviously won't be as cheap as ebay, but if its new stuff you're after give them a shot.
Another one that might be worth a look is
http://www.flightstore.co.uk/
I haven't used them before, only found them a few days ago but if you know what you're after you'll be able to suss out if they're any cheaper.
Hope this helps.