Tubulars tubulars!

so i've got an old 700c tri-spoke which on I seem to be forever replacing the tubulars, riding for about a year/6 months before puncturing then taking forever to replace myself which is a real mission and I'm sure I'm not doing it to the best quality.
So I have a few queries

• I'm looking for one brand new unused tubular that I can buy from you, happy for mid range between £15-30 let me know what you have
  
• Can anyone recommend somewhere or someone who won't charge me £30/40 (which I've been quoted at most bike shops) for fitting it
  
  

Am located in Kew Gardens SW London so nearer the better!

cheers