I have a '94 project big one and the local mechanic tells me I need 2 new front calipers (complete). Worried this will cost many £s. Any advice, are these easy to come by? Are they pricey?

I doubt you need new calipers. More likely that you need to strip them down and do a full refurb. Allow around £15 per piston for OEM seals and around £25 per piston if any need replacing.

I think he's honest. What he's saying is that the aluminium caliper casing has corroded inside and therefore reduces the pistons return. That means the frant brake is gently on at all times, just pinching the disc. It's rideable but I'd sooner sort it. Anyone know where I can buy new calipers? I can't see them online. Maybe there's a cross over with other makes and models, to give me £ options.