DaveSSS 

You need to read the forums more frequently! 11 speed parts can be had for less than 10 speed, if you know where to shop.

I've paid far less for all of my 11 speed parts than the some level of components cost in 2008 10 speed. There are several reputable dealers in the UK that have excellent service and prices. To make the cheapest conversion, most 10 speed cranks and FDs will work, so at the minimum you need shifters, chain, chain tool and cassette. I've bought Chorus shifters for $210, chains for $33 and cassettes for $110. That's only $353. Then sell the old shifters on E-bay for $100 and you've got a conversion for a little over $250. I've also bought new Chorus 11 cranks for $310.

Here are some links to a few sites. I bought most of my parts from Shiny or Ribble (when they had a 15% off sale). I would avoid Bike 24 (poor communication and slow shipping) and comobike. Comobike ships by UPS. UPS charges brockerage fees and seems to get charged unwarranted tariffs that are difficult to challenge and get refunded. Orders from the UK come through the US postal system after they arrive in the US and never seem to get charged unwarranted tariffs. Very few bike parts are subject to tariff. Wheels and frames may have tariffs imposed.

http://www.shinybikes.com/
www.comobike.com
http://www.bike24.com/1.php
http://www.totalcycling.com/
http://www.ribblecycles.co.uk/