After much research I chose Broadleaf Timber. They specialised in Oak flooring, in particular for fitting over under-floor heating. They also offered discount for over 100 sq/m orders. Exactly what I needed! They also supply the oil, brushes, polish, cleaner etc and a very comprehensive briefing sheet. The latter is available before you order.
I also purchased my Suffolk latches from them.
The product was excellent and they are strongly recommended.
Contact them at: www.broadleaftimber.com