At the Total Motorshow (KICC) sometimes in September, CICA Motors had nice buses on display; they don’t do the body building bit but can contract and deliver a complete unit build as per specifications.
and @ Robinhood noted costs vary depending on the type of body.
This is the DUTY PAID quotation send to me from the company;
HD72 Chasis Cab 3,127,000
Options /Accessories
Vehicle Registration 25,000
Bus Body 1,050,000
Total 4,202,000