Try
www.leisurelakesbikes.co.uk in Bury - not too far a drive from Oldham.
They do Zero % over 6, 12, 18 mths depending on how much bike is.
I know they do Cube & Specialized there but can't remember what other brands.
If you join their V.I.P club (at a cost £30) you get 5% off price of new bike + a Muc Off bike cleaning kit with value £30++ @ RRP so a no brainer really.
You don't say what size frame you need or your height leg length reach etc - some here are good @ finding a bargain for folks (not me really) so this would help a little.