Any question answered...

What's the cheapest 52/39 pair of ultegra grey rings or full chainset that anyone can find online?

Wiggle have the full chainset on for £122.91 but I can't find any decent deals for the replacement rings. Anyone aware of any bargains out there?

Those (6700?) rings will be very pricey. Madison website reckons £80 for the outer.

Might be worth getting a Shimano outer and a cheaper alternative for the inner. Or pony up for the chainset and sell yours on for spares / repair.