Hi minimunky, unsure of who stocks the part you need here but thought I'd mention some UK suppliers/links in case you missed any.

http://www.pinballmania.co.uk/ - A personal favourite, contact for parts not listed.
http://www.pinballheaven.co.uk - Good guys also
pinballdaze.co.uk - Welsh based. Not used myself.
And avoid the Blackpool based 'PinballParadise'

Join the uk pinball yahoo group for help,buy or sell,
visit pinformer.co.uk for where to play in the UK and
Pinballinfo.com for a forum style where some people from the yahoo group post...but can be nsfw...

(Personally prefer pinside obviously.)